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Multi-Frequency surface Electrical Impedance Myography (MF-sEIM) is a technique that provides valuable electrophysiological information of muscles. This technique measures bio-Z spectroscopy of muscles, and applies Ohm's law by injecting a small-amplitude and high-frequency current into tissues and measuring the voltage response. As biological tissues are electrolytic conductors, this technique provides information on fundamental dielectric properties of tissues, which are an objective biomarker of neuromuscular disorders and have practical value in several muscle healthcare applications. Due to its versatility, simplicity, and ease of integration, this technique is a great candidate to complement stand-alone surface electromyography (sEMG) in wearable devices for continuous monitoring of muscle health. Nonetheless, wearable MF-sEIM imposes challenging requirements on the bio-Z spectroscopy interface. Previously reported solutions fall short of meeting these requirements, or do so with low power efficiency. This thesis focuses on the research and development of a fully integrated bio-Z spectroscopy interface, which complies with the challenging requirements of wearable MF-sEIM in a power-efficient way. The electrophysiological mechanisms of MF-sEIM and the system-level requirements for clinical relevance were investigated, as MF-sEIM is a relatively novel technique, which requires standarization. From this established set of requirements, the main building blocks of the \mbox{bio-Z} spectroscopy interface, i.e., the current signal generator (CSG), and voltage readout, were developed. The CSG generates pseudo-sine waves through direct digital synthesis (DDS) to obtain the required linearity with high power efficiency. A high-linearity full current-mode CSG was also proposed to comply with the stricter bio-Z accuracy requirements of clinical diagnostics. The voltage readout is based on a low-IF quadrature (I/Q) demodulation architecture and features a pseudo 2-path ba, Multifrekvent ytelektroimpedansmyografi (MF-sEIM) är en teknik som ger värdefull elektrofysiologisk information om muskler. Denna teknik mäter bioimpedans-spektroskopi (bio-Z-spektroskpi) av muskler och tillämpar Ohms lag genom att injicera en högfrekvent småsignalström i vävnader och mäta spänningssvaret. Eftersom biologiska vävnader är elektrolytiska ledare, ger denna teknik information om grundläggande dielektriska egenskaper hos vävnader, som är en objektiv biomarkör för neuromuskulära störningar och har praktiskt värde i flera tillämpningar för muskelsjukvård. På grund av dess mångsidighet och enkel integration är denna teknik en utmärkt kandidat för att komplettera fristående ytelektromyografi (sEMG) i bärbara enheter för kontinuerlig övervakning av muskelhälsa. Icke desto mindre ställer bärbar MF-sEIM utmanande krav på bio-Z-spektroskopigränssnittet. Tidigare rapporterade lösningar uppfyller inte dessa krav, eller gör det med låg energieffektivitet. Denna avhandling fokuserar på forskning och utveckling av ett helt integrerat bio-Z-spektroskopigränssnitt, som uppfyller de utmanande kraven för bärbar MF-sEIM på ett energieffektivt sätt. De elektrofysiologiska mekanismerna för MF-sEIM och kraven på systemnivå för klinisk relevans undersöktes, eftersom MF-sEIM är en relativt ny teknik som kräver standardisering. Från de definerade kraven på systemnivå utvecklades huvudbyggstenarna för bio-Z-spektroskopigränssnittet, dvs. strömsignalgeneratorn (CSG) och spänningsavläsningen. CSG genererar pseudo-sinusvågor genom direkt digital syntes (DDS) för att erhålla den erforderliga linjäriteten med hög energieffektivitet. En CSG i fullströmsläge med hög linjäritet föreslogs också för att uppfylla de striktare noggrannhetskraven på bioimpedansmätning för klinisk diagnostik. Spänningsavläsningen är baserad på en demoduleringsarkitektur med låg IF-kvadratur (I/Q) och har en pseudo 2-vägs bandpass (BP) Delta-Sigma ADC för att uppnå hög precision och energi till brus effektivit, QC 20240829

The field of superconducting circuits has grown dramatically in the last decade and is a leading architecture for quantum computation. Part of this architecture’s success is the simple control, scalability, and increasingly long lifetime of the transmon qubit, which became dominant in most processors. Nevertheless, there will need to be significant improvements in their performance to reach fault-tolerant computation. A major limitation of these qubit operations today is from ‘leakage’, or from populating the higher energy states of the qubit. This process is generally incurred from off-resonant processes, which are hard to capture from both a numerical and theoretical viewpoint, and our understanding of such processes must be improved to continue enhancing these devices. In this thesis, I investigate how we can understand, accurately simulate, and suppress error-causing processes resulting from strong measurement and control drives on transmon qubits. As part of my research, I present a method of efficiently simulating systems in the presence of fast-oscillating drives, and how this allows us to optimize the controls to improve the fidelity of operations. I additionally demonstrate how sufficiently strong measurement drives during readout can not only result in leakage but also in the population of states outside of the transmon's confining potential, which we refer to as `ionization'. I conclude with my work in collaboration with ETH Zurich on state-of-the-art readout results using flux-tunable transmons and Purcell Filters., Le domaine des circuits supraconducteurs a connu une croissance spectaculaire au cours de la dernière décennie et constitue une architecture de premier plan pour l’informatique quantique. Le succès de cette architecture tient en partie à la simplicité du contrôle, à l’évolutivité et à la durée de vie de plus en plus longue du qubit transmon, qui est devenu dominant dans la plupart des processeurs. Bien que la fidélité de la plupart des opérations quantiques sur ces dispositifs dépasse généralement 98− 99%, des améliorations significatives des performances seront nécessaires pour parvenir à un calcul tolérant aux fautes. L’une des principales limites actuelles de ces opérations sur les qubits est due aux “fuites”, c’est-à-dire au peuplement des états d’énergie supérieure du qubit. Ces effets sont difficiles à appréhender d’un point de vue numérique et théorique, car de nombreuses transitions résultent de processus hors résonance qui sont généralement ignorés afin de rendre le problème traitable. En outre, beaucoup de ces effets sont causés par les niveaux d’énergie plus élevés du transmon, présents hors de son potentiel de confinement. Ceux-ci sont également négligés dans les simulations et les études théoriques pour des raisons de simplicité, ce qui entraîne une mauvaise caractérisation de la dynamique. Dans cette thèse, j’étudie comment nous pouvons comprendre, simuler avec précision et supprimer les processus à l’origine d’erreurs résultant de mesures et de contrôles forts sur les qubits transmon. Dans le cadre de ma recherche, je présente une méthode permettant de simuler efficacement des systèmes en présence de commandes à oscillation rapide, et comment celle-ci nous permet d’optimiser les commandes afin d’améliorer la fidélité des opérations. Cette méthode permet une accélération significative par rapport aux intégrateurs numériques traditionnels, et une version de ce solveur est maintenant incluse dans Qiskit Dynamics, un logiciel d’IBM. Je démontre en outre c

Crescente domanda di rivelatori ad alta velocità nella moderna fisica delle alte energie esperimenti sta generando molte sfide tecnologiche. In particolare, i rivelatori di particelle utilizzati negli esperimenti di fisica delle alte energie richiedono sistemi elettronici di lettura efficienti in grado di far fronte alle sfide affrontate a causa dell'aggiornamento negli esperimenti di fisica delle alte energie. I circuiti integrati CMOS, tecnologia ampiamente utilizzata, sono una scelta comune per i chip di lettura basati su fattori di affidabilità, riduzione dei costi e miglioramento delle prestazioni. In questa tesi, vengono presentate informazioni generali sull'esperimento insieme alle sfide imminenti dovute all'aggiornamento previsto nell'esperimento e un nuovo sistema elettronico di lettura, mirato a una notevole efficienza energetica, è un design efficiente, con prestazioni promettenti mirate a sostituire l'esistente viene presentata l'elettronica di lettura. L'elettronica front-end è composta da quattro canali simmetrici in cui ogni canale è una struttura di segnali misti. L'architettura del canale è ottimizzata per ridurre la potenza e l'area del design. Ciascun canale comprende un preamplificatore sensibile alla carica, uno shaper per implementare lo schema di sagomatura bipolare, un discriminatore e driver di segnalazione differenziale a bassa tensione. Il canale proposto funziona con una carica di ingresso di 5–100 fC e mostra una sensibilità lineare di 8 mV/fC per l'intero intervallo di carica di ingresso. Il ritardo di picco del canale analogico è di 14,6 ns. All'uscita, la rappresentazione temporale del segnale di ingresso è fornita in termini di livello CMOS e in segnale a bassa tensione scalabile (SLVS). Il consumo energetico di ciascun canale è di 12,8 mW, ovvero il 61,2% in meno rispetto al modello precedente. Ciascun canale occupa un'area di 0,235 mm2, ovvero solo il 58,75% del design precedente. Il design completo dell'elettronica front, Increasing demand for high-rate detectors in modern High Energy Physics experiments is generating many technological challenges. Particularly, the particle detectors utilized in High Energy Physics experiments requires efficient readout electronics systems that can cope with the challenges faced due to the upgrade in High Energy Physics experiments. CMOS integrated circuits, widely used technology, is a common choice for readout chip based on reliability, cost reduction and performance improvement factors. In this thesis, a general information of the experiment along with the upcoming challenges due to expected upgrade in the experiment are presented and a new readout electronic system, targeting a significantly power efficient, are efficient design, with a promising performance targetting to replace the existing readout electronics is presented. Front end electrinics is composed of four symmetrical channels where each channel is a mixed signal structure. The channel architecture is optimized to reduce the power and area of the design. Each channel comprises a charge-sensitive preamplifier , shaper to implement the bipolar shaping scheme, discriminator and differential low-voltage signaling drivers. The proposed channel operates with a 5–100 fC input charge and exhibits a linear sensitivity of 8 mV/fC for the entire input charge range. The peaking time delay of the analog channel is 14.6 ns. At the output, the time representation of the input signal is provided in terms of the CMOS level and in scalable low-voltage signal (SLVS). The power consumption of each channel is 12.8 mW, which is 61.2 percent lower than in the previous design. Each channel occupies an area of 0.235 mm.sq, which is only 58.75 percent of the previous design. The full 4 channel Front end electronics design is realized in TSMC 65 nm CMOS technology and its die-area is 2 mm by 2 mm. The first part of this thesis presents the LHC experiment information and the classical readout electronics, fabric

DARTWARS (Detector Array Readout with Traveling Wave AmplifieRS) is a three years project that aims to develop high-performing innovative Traveling Wave Parametric Amplifiers (TWPAs) for low temperature detectors and qubit readout (C-band). The practical development follows two different promising approaches, one based on the Josephson junctions (TWJPA) and the other one based on the kinetic inductance of a high-resistivity superconductor (KITWPA). This paper presents the advancements made by the DARTWARS collaboration to produce a first working prototype of a KITWPA.

Superconducting nanowire single-photon detectors are the most promising technology in quantum photon information. They offer high speed, high detection efficiency, low dark count rate as well as low timing jitter compared to other single photon detection solutions. Since the recent advances in photonic quantum computing, the drive for improvement of the implementation complexity, performance and scalability of quantum photon detection has increased. This presents challenges with the current device readout schemes and alternative solutions are required. One of the key parameters to improve the scalability of superconducting nanowire single-photon detectors, is reducing the power dissipation per pixel. This is especially important in cryogenic readouts, where the performance of electronic components changes compared to room temperature. Moreover, the performance of a cryogenic superconducting nanowire single-photon detector readout is dependent both on the device and readout electronics level characteristics, and both must be fine-tuned for desired performance. A solution to the scalability of superconducting nanowire single-photon detectors (SNSPDs) is the development of a readout scheme with minimized power dissipation. We propose a fully digital readout scheme interfaced with a superconducting nanowire single-photon detector (SNSPD), that allows photon detection and reset. For this purpose, a digital single-pixel SiGe Bi-CMOS readout is designed, simulated, and characterised. An improved readout scheme is proposed with an addition of a die resistor to allow a full reset of the detector., Supraledande nanotrådsdetektorer baserade på enstaka fotoner är ett av de mest avancerade koncepten inom kvantfotoninformationsteknik. Syftet med att utveckla denna teknik är att förbättra egenskaper så som komplexiteten, prestandan och skalbarheten. En av de viktigaste parametrarna för att förbättra skalbarheten hos supraledande nanotrådsdetektorer med enstaka fotoner är att minska energiförbrukningen per pixel. Detta är särskilt viktigt i kryogena avläsningar, där prestandan hos elektroniska komponenter förändras jämfört med rumstemperatur. Dessutom, beror prestandan hos en kryogen supraledande nanotrådsdetektor både på komponenten och på avläsningselektroniken,och båda måste finjusteras för att uppnå önskad prestanda. En lösning på kalbarheten för supraledande nanotrådsdetektorer med enstaka fotoner (SNSPDs) är att realisera avläsning med minimerad effektförlust. Vi föreslår en helt digital avläsning som är kopplad till en supraledande enfoton nanotrådsdetektor (SNSPD), som gör det möjligt att detektera fotoner och att återställa detektorn efter avläsning. För detta ändamål, designades, simuleras och karakteriserades en digital avläsningkrets med en enda pixel. Ett förbättrat avläsningssystem föreslås genom att lägga till ett diskret motstånd för att möjliggöra en fullständig återställning av detektorn.

The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data-taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and insitu calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1 +/- 0.9 mu m and a relative momentum resolution sigma(p)/p = (4.83 +/- 0.16) x 10(-4) GeV-1 x p(T) have been measured for high momentum tracks.

The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data-taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1 +/- 0.9 mu m and a relative momentum resolution sigma(p)/p = (4.83 +/- 0.16) x 10(-4) GeV-1 x p(T) have been measured for high momentum tracks.

The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data-taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1 +/- 0.9 mu m and a relative momentum resolution sigma(p)/p = (4.83 +/- 0.16) x 10(-4) GeV-1 x p(T) have been measured for high momentum tracks.

Passive solid state dosimeters, such as thermoluminescence dosimeters, provide integrated measurement of the total dose and are widely used in environmental monitoring programs. The objective of this paper is to provide a comprehensive review on the use of thermoluminescent dosimetry methods for monitoring radiation dose in the environment. The article presents the part of the research results of the project PREPAREDNESS (EMPIR 2016 call for Metrology for Environment joint research project) with a particular objective to harmonize procedures used by dosimetry services, relevant authorities and Institutes across the Europe. To achieve this, different monitoring routines that are based on passive environ mental dosimetry methods are investigated. Differences in performing specific steps such as preheating, reading, annealing, minimizing fading, and others, are analyzed. The investigation was performed by means of qualitative literature review that showed the lack of information about specific steps. The conclusion of this work is that thermoluminescent dosimetry measurement system has to be type-tested even though the testing procedure is complicated. In addition to this, control dosimeters should be introduced, International Organization for Standardization protocols should be followed during calibration, and finally, parameters influencing the measurement uncertainty have to be identified and well understood in order to pro duce ac cu rate dose measurement results.

This thesis focuses on improving the readout of the ADome by implementing MCUs at each antenna probe, enabling local sampling and memory storage. The serial communication protocols CAN, SPI and I2C are considered and compared with one another. Ultimately, CAN is decided due to its robustness and simplicity which make the system cheap and ensures that the measurement will not get corrupted during transmission. Moreover, implementations of the new readout protocol are able to obtain measurement data store information at the local MCU. Test setups verification showed that antenna location can be stored and retrieved. Furthermore, the readout protocol is able to acquire multiple samples from the ADC locally.

People routinely perform multiple visual judgments in the real world, yet, intermixing tasks or task variants during training can damage or even prevent learning. This paper explores why. We challenged theories of visual perceptual learning focused on plastic retuning of low-level retinotopic cortical representations by placing different task variants in different retinal locations, and tested theories of perceptual learning through reweighting (changes in readout) by varying task similarity. Discriminating different (but equivalent) and similar orientations in separate retinal locations interfered with learning, whereas training either with identical orientations or sufficiently different ones in different locations released rapid learning. This location crosstalk during learning renders it unlikely that the primary substrate of learning is retuning in early retinotopic visual areas; instead, learning likely involves reweighting from location-independent representations to a decision. We developed an Integrated Reweighting Theory (IRT), which has both V1-like location-specific representations and higher level (V4/IT or higher) location-invariant representations, and learns via reweighting the readout to decision, to predict the order of learning rates in different conditions. This model with suitable parameters successfully fit the behavioral data, as well as some microstructure of learning performance in a new trial-by-trial analysis.

open, Increasing demand for high rate detectors in modern High Energy Physics experiments is generating many technological challenges. In particular, developments in particle detector technology increased requirements on electronic readout systems and fostered research on integrated readout systems. As a widely used technology, CMOS integrated circuits are a common choice for readout chip. In this thesis some of the major challenges in detector readout are analyzed while reporting novel experimental results on an existent prototype. A new readout system, exploiting a new double threshold signal processing technique, is also presented. The first part of this thesis presents experimental results obtained with GEMINI chip, a readout chip for Triple-GEM detectors fabricated in CMOS 180 nm. After an analysis of major challenges in Triple-GEM readout, results from chip characterization are presented. On detector tests are also reported describing methodologies developed specifically for this system. Furthermore, results from an irradiation test of GEMINI are presented, with an analysis of TID effects on Time-over-Threshold performance. The second part of this thesis presents a new readout chip, FTfe, designed in CMOS 65 nm process. This readout system has been specifically designed for Muon Drift Chambers taking advantage of the know-how acquired during experimental work on GEMINI. After a theoretical analysis of the signal processing technique proposed, the implementation of FTfe is presented in detail. Results from transistor level simulations are eventually presented., La crescente necessità di detector ad alto rate nei moderni esperimenti di Fisica delle Alte Energie genera molte sfide tecnologiche. In particolare, gli sviluppi nella tecnologia dei detector ha aumentato i requisiti sui sistemi di readout e stimolato la ricerca su sistemi integrati di readout. I circuiti integrati CMOS sono largamente diffusi e sono una scelta comune per i chip di readout. In questa tesi vengono analizzati alcune delle maggiorni criticità nel readout di detectors mentre vengono riportati nuovi risultati sperimentali riguardanti prototipi esistenti. Viene inoltre presentato un nuovo sistema di reaout che sfrutta una nuova tecnica di signal processing a doppia soglia. La prima parte di questa tesi presenta risultati sperimentali ottenuti con il chip GEMINI, un chip di readout per rivelatori Triple-GEM fabbricato in CMOS 180 nm. Dopo una analisi delle maggiori sfige nel readout di questi detector, vengono presentati i risultati ottenuti dalla caratterizzazione del chip. Vengono inoltre riportati i risultati di test on detector descrivendo le metodologie sviluppate per questo sistema. Inoltre, vengono presentati i risultati di un test di irraggiamento di GEMINI, con una analisi degli effetti di TID sulla performance di Time ove Threshold. La seconda parte di questa tesi presenta un nuovo chip di readout, FTfe, sviluppato specificamente per camere a muoni, sfruttando il know-how acquisito dalle attività sperimentali su GEMINI. Dopo un analisi teorica della tecnica di signal processing proposta, viene presentata in dettaglio l'implementazione del sistema. Infine vengono presentati i risultati da simulazioni a livello transistor., No, open, Mangiagalli, L

This thesis presents a BJT-based CMOS temperature-to-digital converter (TDC). With a continuous-time readout, the TDC avoids the kT/C noise limit incurred by previous discrete-time (switched-capacitor) TDCs. An energy-efficient BJT front-end generates single PTAT and CTAT currents for being digitized by a delta-sigma modulator through a linear charge-balancing operation. Simulated in a standard 0.18 um CMOS process, the TDC achieves a (3*sigma) inaccuracy of 0.13'C from -40'C to 125'C after one-point trimming. Moreover, the TDC achieves 4 mK resolution in a 202 millisecond conversion time, while consuming 4.9 uW. This corresponds to a resolution FoM of 15.7 pJ.K2., Electrical Engineering | Microelectronics

Quantum computers hold a promise to solve intractable problems that can not be solved with classical computers. In quantum computers, information is processed in qubits as opposed to bits. The proper operation of qubits requires them to be operated in a quantum state; hence they need to be cooled down to temperatures well below <1K. Using qubits and their quantum mechanical property, quantum computers can achieve exponential speedup in solving certain computing problems compared to classical computers. However, this can only be achieved by employing thousands of qubits. At the current state of play, quantum computers are still far from practical. The current state-of-the-art solution dictates that each qubit needs multiple interconnects towards room temperature and requires bulky room temperature instruments for qubit readout and control. Clearly, this current solution will not scale well for a quantum computer with many qubits. In an effort to solve this issue, it has been proposed to realize dedicated integrated circuits for control and readout of the qubits and operate them closer to the qubits' operating temperature to enable scalability. The thesis presents the implementation of an integrated RF receiver for spin and superconducting qubit readout applications. The work aims to replace the bulky room temperature electronics with an integrated solution that operates at 4K to enable scalability and simplification of the quantum computing architecture. The receiver has been designed in the TSMC 40nm CMOS technology and has been characterized in room temperature and 4K. The measured performance shows that the receiver features a gain of 58 dB and a minimum double-sideband noise figure of 0.6 dB at 4K with an operating frequency of 6-8 GHz; a comparable performance to the current state-of-the-art room temperature electronics used for qubit readout. Moreover, this work demonstrates a qubit readout experiment with the integrated receiver in both room temperature

La crescente necessità di detector ad alto rate nei moderni esperimenti di Fisica delle Alte Energie genera molte sfide tecnologiche. In particolare, gli sviluppi nella tecnologia dei detector ha aumentato i requisiti sui sistemi di readout e stimolato la ricerca su sistemi integrati di readout. I circuiti integrati CMOS sono largamente diffusi e sono una scelta comune per i chip di readout. In questa tesi vengono analizzati alcune delle maggiorni criticità nel readout di detectors mentre vengono riportati nuovi risultati sperimentali riguardanti prototipi esistenti. Viene inoltre presentato un nuovo sistema di reaout che sfrutta una nuova tecnica di signal processing a doppia soglia. La prima parte di questa tesi presenta risultati sperimentali ottenuti con il chip GEMINI, un chip di readout per rivelatori Triple-GEM fabbricato in CMOS 180 nm. Dopo una analisi delle maggiori sfige nel readout di questi detector, vengono presentati i risultati ottenuti dalla caratterizzazione del chip. Vengono inoltre riportati i risultati di test on detector descrivendo le metodologie sviluppate per questo sistema. Inoltre, vengono presentati i risultati di un test di irraggiamento di GEMINI, con una analisi degli effetti di TID sulla performance di Time ove Threshold. La seconda parte di questa tesi presenta un nuovo chip di readout, FTfe, sviluppato specificamente per camere a muoni, sfruttando il know-how acquisito dalle attività sperimentali su GEMINI. Dopo un analisi teorica della tecnica di signal processing proposta, viene presentata in dettaglio l'implementazione del sistema. Infine vengono presentati i risultati da simulazioni a livello transistor., Increasing demand for high rate detectors in modern High Energy Physics experiments is generating many technological challenges. In particular, developments in particle detector technology increased requirements on electronic readout systems and fostered research on integrated readout systems. As a widely used technology, CMOS integrated circuits are a common choice for readout chip. In this thesis some of the major challenges in detector readout are analyzed while reporting novel experimental results on an existent prototype. A new readout system, exploiting a new double threshold signal processing technique, is also presented. The first part of this thesis presents experimental results obtained with GEMINI chip, a readout chip for Triple-GEM detectors fabricated in CMOS 180 nm. After an analysis of major challenges in Triple-GEM readout, results from chip characterization are presented. On detector tests are also reported describing methodologies developed specifically for this system. Furthermore, results from an irradiation test of GEMINI are presented, with an analysis of TID effects on Time-over-Threshold performance. The second part of this thesis presents a new readout chip, FTfe, designed in CMOS 65 nm process. This readout system has been specifically designed for Muon Drift Chambers taking advantage of the know-how acquired during experimental work on GEMINI. After a theoretical analysis of the signal processing technique proposed, the implementation of FTfe is presented in detail. Results from transistor level simulations are eventually presented.

This thesis presents a BJT-based CMOS temperature-to-digital converter (TDC). With a continuous-time readout, the TDC avoids the kT/C noise limit incurred by previous discrete-time (switched-capacitor) TDCs. An energy-efficient BJT front-end generates single PTAT and CTAT currents for being digitized by a delta-sigma modulator through a linear charge-balancing operation. Simulated in a standard 0.18 um CMOS process, the TDC achieves a (3*sigma) inaccuracy of 0.13'C from -40'C to 125'C after one-point trimming. Moreover, the TDC achieves 4 mK resolution in a 202 millisecond conversion time, while consuming 4.9 uW. This corresponds to a resolution FoM of 15.7 pJ.K2., Electrical Engineering | Microelectronics

For the Phase-II Upgrade of the ATLAS Detector [1], its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100% silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-250) [2, 3] and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.

When chopping is applied to a continuous-time sigmadelta modulator (CTΣΔM), quantization noise fold-back often occurs, leading to increased in-band noise. This can be prevented by employing a return-to-zero (RZ) digital-to-analog converter (RZ DAC) in the modulator's feedback path and arranging the chopping transitions to coincide with its RZ phases. In this letter, this technique has been extended and implemented in an energy-efficient CTΣΔM intended for the readout of Wheatstone bridge sensors. To achieve a wide common-mode input range, the modulator's summing node is implemented as an embedded capacitively coupled instrumentation amplifier which can be readily combined with a highly linear 1-bit capacitive RZ DAC. Measurements show that the proposed chopping scheme does not suffer from quantization noise fold-back and also allows a flexible choice of chopping frequency. When chopped at one-tenth of the sampling frequency, the modulator achieves 15 ppm INL, 4.5 nV/√Hz input-referred noise and a state-of-the-art noise efficiency factor of 6.1., Accepted Author Manuscript, Electronic Instrumentation, Microelectronics

ALICE (A Large Ion Collider Experiment) is the heavy-ion experiment at the Large Hadron Collider (LHC) at CERN. As an important part of its upgrade plans, the ALICE experiment will schedule the installation of a new Inner Tracking System (ITS) during the Long Shutdown 2 (LS2) of the LHC. The new ITS layout will consist of seven concentric layers, ¿ 12.5 Gigapixel camera covering about 10m2 with Monolithic Active Pixel Sensors (MAPS). This choice of technology has been guided by the tight requirements on the material budget of 0.3% X/X0 per layer for the three innermost layers and backed by the significant progress in the field of MAPS in recent years. The technology initially chosen for the ITS upgrade is the TowerJazz 180 nm CMOS Technology. It offers a standard epitaxial layer of 15 - 18 µm with a resistivity between 1 and 5 k¿ cm¿1 and a gate oxide thickness below 4 nm, thus being more robust to Total Ionizing Dose (TID). The main subject of this thesis is to implement a novel digital pixel readout architecture for MAPS. This thesis aims to study this novel readout architecture as an alternative to the rolling-shutter readout. However, this must be investigated through the study of several chip readout architectures during the R&D phase. Another objective of this thesis is the study and characterization of TowerJazz, if it meets the Non-Ionizing Energy Loss (NIEL) and Single Event Effects (SEE) of the ALICE ITS upgrade program. Other goals of this thesis are: ¿ Implementation of the top-down flow for this CMOS process and the design of multiple readouts for different prototypes up to the assembly of a full-scale prototype. xvii Abstract ¿ Characterization of the radiation hardness and SEE of the chips submitted to fabrication. ¿ Characterization of full custom designs using analog simulations and the generation of digital models for the simulation chain needed for the verification process. ¿ Implementation and study of different digital readouts to meet the ITS u, El sub detector ITS (Inner Tracking System) del detector ALICE (A Large Ion Collider Experiment) es un detector de vértice y es el detector mas cercano al punto de interacción. Se encuentra conformado por 3 tipos de subdetectores, dos capas de pixel de silicio (Silicon Pixel Detectors), 2 capas de acumulación de silicio (Silicon Drift Detectors) y 2 capas de banda de Silicio (Silicon Strip Detectors). La función primaria del ITS es identificar y rastrear las partículas de bajo momentum transversal. El detector ITS en sus dos capas más internas están equipadas con sensores de silicio basados en píxeles híbridos. Para reemplazar esta tecnología de Píxeles, el detector ITS actual será reemplazado por un nuevo detector de una sola tecnología, ampliando su resolución espacial y mejorando el rastreo de trazas. Este nuevo detector constará de siete capas de sensores de píxeles activos monolíticos (MAPS), las cuales deberán satisfacer los requerimientos de presupuesto de materiales y ser tolerantes a mayores niveles de radiación para los nuevos escenarios de incrementos de luminosidad y mayores tasas de colisiones. Los sensores MAPS que integran el sensor de imagen y los circuitos de lectura se encuentran en la misma oblea de silicio, tienen grandes ventajas en una buena resolución de posición y un bajo presupuesto material en términos de bajo coste de producción. TowerJazz ofrece la posibilidad de una cuádruple-WELL aislando los transistores pMOS que se encuentran en la misma nWELL evitando la competencia con el electrodo de recolección, permitiendo circuitos mas complejos y compactos para ser implementados dentro de la zona activa y además posee una capa epitaxial de alta resistividad. Esta tecnología proporciona una puerta de óxido muy delgado limitando el daño superficial por la radiación haciéndolo adecuado para su uso denxiii Resúmen tro del experimento ALICE. En los últimos cuatro años se ha llevado a cabo una intensiva I+D en MAPS en el marco de la actualización del, El subdetector ITS (Inner Tracking System) del detector ALICE (A Large Ion Collider Experiment) és un detector de vèrtex i és el detector mes proper al punt d'interacció. Es troba conformat per 3 tipus de subdetectors, dues capes de píxel de silici (Silicon Pixel Detectors), 2 capes d'acumulació de silici (Silicon Drift Detectors) i 2 capes de banda de Silici (Silicon Strip Detectors). La funció primària del ITS és identificar i rastrejar les partícules de baix moment transversal. El detector ITS en les seues dues capes més internes estan equipades amb sensors de silici basats en píxels híbrids. Per a reemplaçar aquesta tecnologia de Píxels, el detector ITS actual serà reemplaçat per un nou detector d'una sola tecnologia, ampliant la seua resolució espacial i millorant el rastreig de traces. Aquest nou detector constarà de set capes de sensors de píxels actius monolítics (MAPS), les quals hauran de satisfer els requeriments de pressupost de materials i ser tolerants a majors nivells de radiació per als nous escenaris d'increments de lluminositat i majors taxes de col·lisions. Els sensors MAPS que integren el sensor d'imatge i els circuits de lectura es troben en la mateixa hòstia de silici, tenen grans avantatges en una bona resolució de posició i un baix pressupost material en termes de baix cost de producció. TowerJazz ofereix la possibilitat d'una quàdruple-WELL aïllant els transistors pMOS que es troben en la mateixa nWELL evitant la competència amb l'elèctrode de recol·lecció, permetent circuits mes complexos i compactes per a ser implementats dins de la zona activa i a més posseeix una capa epitaxial d'alta resistivitat. Aquesta tecnologia proporciona una porta d'òxid molt prim limitant el dany superficial per la radiació fent-ho adequat per al seu ús dins de l'- experiment ALICE. En els últims quatre anys s'ha dut a terme una intensiva R+D en MAPS en el marc de l'actualització del ITS d'ALICE. Diversos prototips a petita escala s'han desenvolupat i provat ix

open, Physic researches and discoveries depend heavily from efficient and reliability of the High-Energy Physics (HEP) experiments. The main goal is to study the fundamental constituents of the matter in terms of elementary charge particles, their interactions and their secondary products. The Large Hadron Collider (LHC) at the CERN works every day to discover details on new charged particles as neutrinos and Higgs Bosons. Charges are generated and accelerated from beam collisions inside the LHC. Different detectors are organized in shell structures and are designed to detect few particles topology. Typically, the parameters useful to identify a charged particle are momentum, electrical charge, energy, time of flight and distance. Detectors design is important but it is enhanced from proper electronic readout systems. In the last years, electronics parts are more and more efficient and compact. CMOS integrated solution are preferred to discrete one allowing major reliability, cost reduction and performance improvement. The design is not trivial but not impossible. Some characteristics depend on the electronic designer and his capability to manage the external parasitic effects, as the parasitic capacitance of the connected detector. Unfortunately, phenomena as radiation effects on electronics must be taken in account but they are not completely eliminated. CMOS technology influences strongly the integrated circuit performance and radiation hardness. In this scenario, 3 readout frontend circuits for HEP experiments have been designed, integrated and measured. 2 of them represent 2 different prototypes realized in IBM 130nm technology for ATLAS experiment at CERN laboratory with Max-Plank Institute for Physics collaboration. They include an analog chain in cascade with a digital one. Input charges (up to 100fC) are detected and converted into voltage signals. Their amplitude are proportional to the input and are sent to the following digital part. The digital part provides, Le ricerche e le scoperte fatte nell'ambito della fisica sono fortemente dipendenti dall'efficienza e dall'affidabilità degli esperimenti ad alta energia. L'obiettivo principale è lo studio delle particelle che costituiscono la materia in termini di cariche elementari, loro interazioni e prodotti secondari che ne possono derivare. L'LHC (Large Hadron Collider) lavora al CERN ogni giorno con l’obiettivo di scoprire nuovi dettagli su particelle cariche come neutroni e Bosoni di Higgs. Queste sono generate e accelerate all’interno dell’LHC e vengono rilevate da opportuni detector organizzati in una struttura a shell. In questo modo, è possibile avere una caratterizzazione in termini di momento, carica elettrica, energia, tempo di volo e distanza associati alla particella rilevata. La progettazione dei rilevatori è importante come anche quella dell’elettronica vicina. Un grande esperimento richiede un duro lavoro di scienziati e ingegneri. Negli ultimi anni, l’elettronica è sempre più efficiente e compatta grazie alla sostituzione dei componenti discreti con circuiti integrati CMOS. La progettazione deve essere però fatta considerando sia le reti di interfacciamento con i sensori sia l’ambiente radiattivo circostante. Le radiazioni, infatti, possono modificare parzialmente o totalmente le performance e la scelta della tecnologia scalata può però essere di grande aiuto. In questo scenario, sono stati progettati, integrati e misurati 3 circuiti di lettura per esperimenti di fisica delle alte energie. 2 prototipi sono stati realizzati in tecnologia 130nm per l'esperimento ATLAS in collaborazione dell’Istituto Max-Plank di Monaco. Questi prototipi sono pensati per rilevare cariche fino a 100fC e convertirle in un segnale di tensione di ampiezza variabile che sarà processato in digitale per avere informazioni sull’istante di arrivo della carica e sulla sua intensità. A tal fine, gli integrati hanno uno stadio di discriminazione ed un Wilkinson ADC in grado di convertire in u, No, open, Resta, F, Resta, F

Majorana zero modes have been proposed as building blocks of intrinsically fault-tolerant quantum computers. Currently, externally applied magnetic fields are necessary to induce Majorana zero modes in carefully engineered systems. Topological qubit state readout is realized by parity sensing of Majorana islands. However, fast and high fidelity conventional cQED parity readout is incompatible with the magnetic fields needed for Majorana physics. In this thesis, magnetic field insensitive microwave CPW resonators with artificial Abrikosov vortex pinning sites have tested and implemented in a graphene based transmon qubit. It has been shown that these artificial pinning sites reliably trap vortices and are able to retain their zero field Qi ~ 105 up to perpendicular fields of 35 mT. By application of these resonators, we have described the successful continuous wave qubit spectroscopy of a graphene transmon qubit at B|| = 1 T with a minimal linewidth of 166 MHz and demonstrated manipulation of the qubit frequency between 3.2-7 GHz with electric field. This is the first ever measured superconducting qubit that shows these properties at a magnetic field of 1 T., Applied Physics

Le ricerche e le scoperte fatte nell'ambito della fisica sono fortemente dipendenti dall'efficienza e dall'affidabilità degli esperimenti ad alta energia. L'obiettivo principale è lo studio delle particelle che costituiscono la materia in termini di cariche elementari, loro interazioni e prodotti secondari che ne possono derivare. L'LHC (Large Hadron Collider) lavora al CERN ogni giorno con l’obiettivo di scoprire nuovi dettagli su particelle cariche come neutroni e Bosoni di Higgs. Queste sono generate e accelerate all’interno dell’LHC e vengono rilevate da opportuni detector organizzati in una struttura a shell. In questo modo, è possibile avere una caratterizzazione in termini di momento, carica elettrica, energia, tempo di volo e distanza associati alla particella rilevata. La progettazione dei rilevatori è importante come anche quella dell’elettronica vicina. Un grande esperimento richiede un duro lavoro di scienziati e ingegneri. Negli ultimi anni, l’elettronica è sempre più efficiente e compatta grazie alla sostituzione dei componenti discreti con circuiti integrati CMOS. La progettazione deve essere però fatta considerando sia le reti di interfacciamento con i sensori sia l’ambiente radiattivo circostante. Le radiazioni, infatti, possono modificare parzialmente o totalmente le performance e la scelta della tecnologia scalata può però essere di grande aiuto. In questo scenario, sono stati progettati, integrati e misurati 3 circuiti di lettura per esperimenti di fisica delle alte energie. 2 prototipi sono stati realizzati in tecnologia 130nm per l'esperimento ATLAS in collaborazione dell’Istituto Max-Plank di Monaco. Questi prototipi sono pensati per rilevare cariche fino a 100fC e convertirle in un segnale di tensione di ampiezza variabile che sarà processato in digitale per avere informazioni sull’istante di arrivo della carica e sulla sua intensità. A tal fine, gli integrati hanno uno stadio di discriminazione ed un Wilkinson ADC in grado di conv, Physic researches and discoveries depend heavily from efficient and reliability of the High-Energy Physics (HEP) experiments. The main goal is to study the fundamental constituents of the matter in terms of elementary charge particles, their interactions and their secondary products. The Large Hadron Collider (LHC) at the CERN works every day to discover details on new charged particles as neutrinos and Higgs Bosons. Charges are generated and accelerated from beam collisions inside the LHC. Different detectors are organized in shell structures and are designed to detect few particles topology. Typically, the parameters useful to identify a charged particle are momentum, electrical charge, energy, time of flight and distance. Detectors design is important but it is enhanced from proper electronic readout systems. In the last years, electronics parts are more and more efficient and compact. CMOS integrated solution are preferred to discrete one allowing major reliability, cost reduction and performance improvement. The design is not trivial but not impossible. Some characteristics depend on the electronic designer and his capability to manage the external parasitic effects, as the parasitic capacitance of the connected detector. Unfortunately, phenomena as radiation effects on electronics must be taken in account but they are not completely eliminated. CMOS technology influences strongly the integrated circuit performance and radiation hardness. In this scenario, 3 readout frontend circuits for HEP experiments have been designed, integrated and measured. 2 of them represent 2 different prototypes realized in IBM 130nm technology for ATLAS experiment at CERN laboratory with Max-Plank Institute for Physics collaboration. They include an analog chain in cascade with a digital one. Input charges (up to 100fC) are detected and converted into voltage signals. Their amplitude are proportional to the input and are sent to the following digital part. The digital part provides

This dissertation spans two topics relating to optical tonear-infrared astronomical cameras built around Microwave KineticInductance Detectors (MKIDs). The first topic is the development of adigital readout system for 10- to 30-kilopixel arrays of MKIDs. MKIDs aresuperconducting detectors that can detect individual photons with a widerange of wavelengths with high time resolution (\SI{2}{\micro s}) and low energyresolution. The advantage of MKIDs over other low temperature detectors with similar capabilities is that it is relatively straightforward to multiplex MKIDs into largearrays. All the complexity of readout is in room temperature electronics.This work discusses the implementation and programming of theseelectronics.The second part of this work demonstrates the capabilities of the prototypeoptical and near-infrared MKID instrument with observations ofpulsars. Detecting optical pulsations in these objects require high timeresolution and low noise. The discovery of a correlation between thebrightness of optical pulses from the Crab pulsar and the time of arrivalof coincident giant radio pulses is presented. The search for opticalpulses from a millisecond pulsar J0337+1715 is discussed along with a newupper limit on the brightness of its optical pulses.

In this paper we present the results of our 176-pixel prototype of the FDM readout system for SAFARI, a TES-based focal-plane instrument for the far-IR SPICA mission. We have implemented the knowledge obtained from the detailed study on electrical crosstalk reported previously. The effect of carrier leakage is reduced by a factor two, mutual impedance is reduced to below 1 nH and mutual inductance is removed. The pixels are connected in stages, one quarter of the array half of the array and the full array, to resolve intermediate technical issues. A semi-automated procedure was incorporated to find all optimal settings for all pixels. And as a final step the complete array has been connected and 132 pixels have been read out simultaneously within the frequency range of 1-3.8MHz with an average frequency separation of 16kHz. The noise was found to be detector limited and was not affected by reading out all pixels in a FDM mode. With this result the concept of using FDM for multiplexed bolometer read out for the SAFARI instrument has been demonstrated., QN/Gao Lab

4400, open, One of the most active research branches in GEM detectors is frontend performance improvement, employing dedicated CMOS integrated solutions, suitable to sustain overall count rate while reducing power consumption, and at the same time increasing system portability. In fact, the development of an ASIC can afford several advantages with respect to other common solutions, i.e. PCBs. For instance, the inclusion of a digital-based data elaboration can greatly increase performance reducing the overall readout system complexity, limiting the necessity of off-chip devices like FPGAs or standard microcontrollers. Then, silicon implementation allows dedicated circuital/system-level choices, optimizing the system to cope with detector performance. Improvements in portability are also crucial, since the detector pixelated output includes hundreds of pads, manufactured in different size factors. These represent a primary issue in readout design, in terms of noise and efficiency. In this scenario, two prototypes with different targets have been developed. The aim of GEMMA (GEM Mixed-signal Asic) is to measure the arrival time and the amount of charge from the Triple-GEM detector. It composes of 8 detecting channels including a Charge Sensitive Preamplifier (CSP) and a Charge-Time Converter (CTC). It is able to manage up to 15pF of pixel parasitic capacitance. The embedded calibration system tunes all channels’ CSP feedback capacitances, to match the target sensitivity of 0.5mV/fC within a 5% tolerance. The CTC converts the CSP output voltage signal into digital domain. In detail, the CTC gets the CSP output and generates two logic output signals. The first, named Charge-Time Signal (CTS), includes information into its time duration, directly proportional to the input charge. The second, named Event Detection Signal (EDS) gives information about the arrival time of the incident particle. In channel 6, for prototyping concern, the CTS is also converted into a 7-bit digital word by, No, open, Pezzotta, Pezzotta, A

One of the most active research branches in GEM detectors is frontend performance improvement, employing dedicated CMOS integrated solutions, suitable to sustain overall count rate while reducing power consumption, and at the same time increasing system portability. In fact, the development of an ASIC can afford several advantages with respect to other common solutions, i.e. PCBs. For instance, the inclusion of a digital-based data elaboration can greatly increase performance reducing the overall readout system complexity, limiting the necessity of off-chip devices like FPGAs or standard microcontrollers. Then, silicon implementation allows dedicated circuital/system-level choices, optimizing the system to cope with detector performance. Improvements in portability are also crucial, since the detector pixelated output includes hundreds of pads, manufactured in different size factors. These represent a primary issue in readout design, in terms of noise and efficiency. In this scenario, two prototypes with different targets have been developed. The aim of GEMMA (GEM Mixed-signal Asic) is to measure the arrival time and the amount of charge from the Triple-GEM detector. It composes of 8 detecting channels including a Charge Sensitive Preamplifier (CSP) and a Charge-Time Converter (CTC). It is able to manage up to 15pF of pixel parasitic capacitance. The embedded calibration system tunes all channels’ CSP feedback capacitances, to match the target sensitivity of 0.5mV/fC within a 5% tolerance. The CTC converts the CSP output voltage signal into digital domain. In detail, the CTC gets the CSP output and generates two logic output signals. The first, named Charge-Time Signal (CTS), includes information into its time duration, directly proportional to the input charge. The second, named Event Detection Signal (EDS) gives information about the arrival time of the incident particle. In channel 6, for prototyping concern, the CTS is also converted into a 7-bit digital word by

GEMINI is a readout ASIC dedicated to the Triple-GEM detector. Fabricated in CMOS 180 nm technology, GEMINI pushes towards the state-of-the-art for this peculiar detector front-end, as regards the count rate and detector pixel parasitic capacitance sustainability. It features 16 channels, each one including a charge-sensitive preamplifier, an event discriminator with channel-independent threshold and an event-triggered reset. An embedded automatic calibration unit compensates performance for environmental, CMOS process and supply voltage variations. GEMINI sustains a 5Mcps count rate, managing up to 40 pF GEM detector capacitance and consuming 2.7mW/ch.

An EJ-299-34 plastic scintillator with silicon photomultiplier (SiPM) readout was used to measure the fast neutron output of a pulsed Thermo-Fisher A-325 Deuterium-Tritium sealed tube neutron generator (STNG). The SiPM signals were handled by a prototype digital pulse processing system, based on a free-running analogue to digital converter feeding a digital signal processor (DSP). Pulse shape discrimination was used to distinguish between detected fast-neutrons and gammas. Pulse detection, timing, energy and shape were all processed by the DSP in real-time.

In this paper a Charge-Sensitive Preamplifier (CSP) for GEM (Gas Electron Multiplier) detectors readout is presented. The CSP is responsible for signal acquisition and the conversion of the input charge into a voltage signal. The design has been realized in 0.13 mu m CMOS technology. It has been demonstrated through a detailed analysis that this is the best CMOS technology to be used in this case, as regards power consumption, intrinsic gain, noise and radiation hardness. The aim is to reduce the power consumption while maintaining other performance at the state-of-the-art. The preamplifier is composed by a three-stage nested Miller Operational Amplifier, with a feed-forward compensation. The system is able to manage a 15 pF detector capacitance. The global power consumption is 1.1 mW and the Equivalent Noise Charge is 418 e(-)

Practical implementation of large SPAD-based sensor arrays in the standard CMOS process has been fraught with challenges due to the many performance trade-offs existing at both the device and the system level [1]. At the device level the performance challenge stems from the suboptimal optical characteristics associated with the standard CMOS fabrication process. The challenge at the system level is the development of monolithic readout architecture capable of supporting the large volume of dynamic traffic, associated with multiple single-photon pixels, without limiting the dynamic range and throughput of the sensor. Due to trade-offs in both functionality and performance, no general solution currently exists for an integrated single-photon sensor in standard CMOS single photon sensing and multi-photon resolution. The research described herein is directed towards the development of a versatile high performance integrated SPAD sensor in the standard CMOS process. Towards this purpose a SPAD device with elongated junction geometry and a perimeter field gate that features a large detection area and a highly reduced dark noise has been presented and characterized. Additionally, a novel front-end system for optimizing the dynamic range and after-pulsing noise of the pixel has been developed. The pixel is also equipped with an output interface with an adjustable pulse width response. In order to further enhance the effective dynamic range of the pixel a theoretical model for accurate dead time related loss compensation has been developed and verified. This thesis also introduces a new paradigm for electrical generation and encoding of the SPAD array response that supports fully digital operation at the pixel level while enabling dynamic discrete time amplitude encoding of the array response. Thus offering a first ever system solution to simultaneously exploit both the dynamic nature and the digital profile of the SPAD response. The array interface, comprising of multiple d

We present details of the construction and characterisation of a prototype thin-tile plastic scintillation detector for use in a multi-layer Fast Neutron Tracker. Scintillation light is read out using solid-state silicon photomultiplier detectors (SiPMs). The Tracker consists of alternating scintillator and Timepix detector layers. The scintillator tile provides a hydrogen-rich target, in which impinging fast neutrons produce recoil protons. The energies lost by protons in the plastic scintillator are measured and recoil protons exiting the scintillator are tracked in the Timepix detector. The combination of signals from the scintillator and Timepix provides information to reconstruct the energy or direction of the impinging neutron, using calculations based on the kinematics of the elastic neutron scattering. Three prototype scintillation detectors were constructed, using either a pair of 3 × 3 mm sensitive area SPMMicro3035 SiPMs from SensL or a pair of MAPD-3n SiPMs from Zecotek. The detector performances were characterised using a mono-energetic proton beam. An absolute energy calibration was measured at 3, 4 and 5 MeV proton energies with good linearity. The best measured energy resolution was 29.8% at 5 MeV. Spatial uniformity was assessed by measuring the response across the detector face. Finally, the tile detector's ability to provide a trigger for Timepix acquisition in the stack configuration was demonstrated for single and double neutron recoil events using a DT neutron source. The SiPM-based design was found to be well-suited for the application of the multi-layer fast neutron tracker.

An upgrade proposal for the LHCb RICH detectors at the Large Hadron Collider at CERN is being developed at the INFN section of Milano Bicocca, based on multi-anode photomultiplier tubes. The application requires the fast readout of Cherenkov rings of photons, with single photon sensitivity, at an event rate up to 40 MHz. The proposed readout chain is tailored for the R7600 multi-anode photomultiplier tubes from Hamamatsu, which proved to fit the single photon sensitivity requirement. The readout electronics for each pixel will be composed of an analog pulse shaper, a binary discriminator and additional digital circuitry to count the pulses. A prototype of the analog shaper was built with commercial discrete transistors in Silicon–Germanium (SiGe) Heterojunction technology. The tradeoff between response speed and power dissipation was investigated; and power as low as a few mW per channel could be achieved with response times of the order of one nanosecond. Furthermore, noise and jitter were evaluated, showing very good performances of the prototype

The objective of this study is to investigate a high performance and lower cost compact gamma camera module for a multi-head small animal SPECT system. A compact camera module was developed using a thin Lutetium Oxyorthosilicate (LSO) scintillation crystal slice coupled to a Hamamatsu H8500 position sensitive photomultiplier tube (PSPMT). A two-stage charge division readout board based on a novel sub-tractive resistive readout with a truncated center-of-gravity (TCOG) positioning method was developed for the camera. The performance of the camera was evaluated using a flood 99mTc source with a four-quadrant bar-mask phantom. The preliminary experimental results show that the image shrinkage problem associated with the conventional resistive readout can be effectively overcome by the novel subtractive resistive readout with an appropriate fraction subtraction factor. The response output area (ROA) of the camera shown in the flood image was improved up to 34%, and an intrinsic spatial resolution better than 2 mm of detector was achieved. In conclusion, the utilization of a continuous scintillation crystal and a flat-panel PSPMT equipped with a novel subtractive resistive readout is a feasible approach for developing a high performance and lower cost compact gamma camera.

This work is aimed at developing a novel simplified readout circuit for 2×2 H8500 multi-anode PSPMT array.The readout scheme is based on two-stage resistive networks with truncated center of gravity(TCOG) positioning method to optimize the detector performance.Test results showed that the readout circuit,which reduces the readout channels from 256 to 4,could well resolve the 1.2 mm crystal elements of the NaI(Tl) crystal array,with maximized effective field-of-view(FOV) of the detector,covering the entire active area of the detector.However,the optical coupling measures in the gap regions between the PSPMTs are necessary,so as to improve image distortion in the gap regions.The results indicate that our design is effective and can be adopted for high-resolution gamma camera with even larger FOV.

The aim of this study was to develop a highperformance simplified readout electronic for a compact gamma camera to achieve a maximized performance in its intrinsic spatial resolution. This compact camera is based on a pixellated NaI(Tl) crystal with 1.2 mm×1.2 mm×5 mm pixel element and 1.4 mm pixel pitch coupled to a 2×2 Hamamatsu H8500 multi-anode position sensitive photomultiplier tube (PSPMT) array. The design of the simplified readout is based on novel two-stage charge divisions with Truncated Center-of-Gravity (TCOG) positioning method to maximize the detector performance. The performance of the compact camera with the novel simplified readout was evaluated by flood imaging of a 57Co source. The experimental results show that the readout circuits we developed can effectively reduce the readout channels from 256 to 4 and well resolve the 1.2 mm crystal elements of the NaI(Tl) crystal array while maximizing the effective field-of-view (FOV) of the detector to cover the whole active area of the detector. In addition, the optical coupling measures in the gap regions among the PSPMT array are necessary in order to improve the image distortion in the gap regions. The results indicate that our design is effective approach which can be adopted for other highresolution gamma camera based on multi-anode PSPMT array with a larger FOV.

Humans and other primates can rapidly categorize objects even when they are embedded in complex visual scenes (Thorpe et al., 1996; Fabre-Thorpe et al., 1998). Studies by Serre et al., 2007 have shown that the ability of humans to detect animals in brief presentations of natural images decreases as the size of the target animal decreases and the amount of clutter increases, and additionally, that a feedforward computational model of the ventral visual system, originally developed to account for physiological properties of neurons, shows a similar pattern of performance. Motivated by these studies, we recorded single- and multi-unit neural spiking activity from macaque superior temporal sulcus (STS) and anterior inferior temporal cortex (AIT), as a monkey passively viewed images of natural scenes. The stimuli consisted of 600 images of animals in natural scenes, and 600 images of natural scenes without animals in them, captured at four different viewing distances, and were the same images used by Serre et al. to allow for a direct comparison between human psychophysics, computational models, and neural data. To analyze the data, we applied population "readout" techniques (Hung et al., 2005; Meyers et al., 2008) to decode from the neural activity whether an image contained an animal or not. The decoding results showed a similar pattern of degraded decoding performance with increasing clutter as was seen in the human psychophysics and computational model results. However, overall the decoding accuracies from the neural data lower were than that seen in the computational model, and the latencies of information in IT were long (~125ms) relative to behavioral measures obtained from primates in other studies. Additional tests also showed that the responses of the model units were not capturing several properties of the neural responses, and that detecting animals in cluttered scenes using simple model units based on V1 cells worked almost as well as using more complex mode

The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope began its on-orbit operations on June 23, 2008. Calibrations, defined in a generic sense, correspond to synchronization of trigger signals, optimization of delays for latching data, determination of detector thresholds, gains and responses, evaluation of the perimeter of the South Atlantic Anomaly (SAA), measurements of live time, of absolute time, and internal and spacecraft boresight alignments. Here we describe on-orbit calibration results obtained using known astrophysical sources, galactic cosmic rays, and charge injection into the front-end electronics of each detector. Instrument response functions will be described in a separate publication. This paper demonstrates the stability of calibrations and describes minor changes observed since launch. These results have been used to calibrate the LAT datasets to be publicly released in August 2009., QC 20100525QC 20151209

To develop high resolution gamma camera, a novel readout method is adopted. The detector of the gamma camera is based on CsI(Na) scintillation crystal array coupling with position-sensitive photomultiplier (PSPMT). The novel readout scheme utilizes the truncated center-of-gravity (TCOG) method, which hybridizes the conventional resistive readout and the individual analogue readout. The TCOG design was tested on a readout circuit board made by ourselves. As a result, the gamma camera could achieve an intrinsic spatial-resolution of 1 mm. The field-of-view (FOV) was also improved to cover the active area of the detector. In conclusion, the TCOG method is an effective approach to developing high-resolution compact gamma camera. This method can also be used in the newly high-integrated multi-anode PSPMT.

The purpose of this study was to investigate an optimal readout for a high-resolution compact gamma camera with maximum performance in crystal element identifications. The compact camera is based on a pixellated Nal(Tl) crystal with 1.2 mm pixel size coupled to a 5" Hamamatsu R3292 PSPMT. A conventional resistive-chain readout was initially developed for the camera. Then a novel subtractive resistive readout developed was utilized to optimize the performance of the camera. The performance of the camera was evaluated by raw flood images of a 137Cs source. The results show that the conventional resistive readout results in a significant shrinkage of the useful field-of- view (UFOV) of the detector with a maximum of resolvable crystal elements of 64times64, which is about 89% of the active-area of the PSPMT's (~10 cm). The subtractive resistive readout can maximize the crystal element identifications up to 71times71 while improve the UFOV of the detector up to almost the full active- area of the PSPMT's. In the central region of the camera, the subtractive resistive readout also improve the peak-valley ratio of the crystal elements from 1.5:1 to 2:1 as compared the conventional resistive readout. The phantom and in vivo mouse imaging studies demonstrate that the compact camera with subtractive resistive readout can provide very good performance for high-resolution SPECT. We concluded that the subtractive resistive readout is an effective approach for an optimal readout for the development of high-resolution compact gamma cameras.

Josephson junction qubits are promising candidates for a scalable quantum processor. Such qubits are commonly manipulated by means of sequences of rf-pulses and different methods are used to determine their quantum state. The readout should be able to distinguish the two qubit states with high accuracy and be faster than the relaxation time of the qubit. We discuss and experiment with a readout method based on the switching of a Josephson junction from the zero voltage state to a finite voltage state. The Josephson junction circuit has a non-linear dynamics and when it is brought to a bifurcation point, it can be made arbitrarily sensitive to small perturbations. This extreme sensitivity at a bifurcation point can be used to distinguish the two quantum states if the topology of the phase space of the circuit leads to a quick separation into the final states where re-crossings of the bifurcation point are negligible. We optimize a switching current detector by analyzing the phase space of a Josephson junction circuit with frequency dependent damping. A pulse and hold technique is used where an initial current pulse brings the junction close to its bifurcation point and the subsequent hold level is used to give the circuit enough time to evolve until the two states can be distinguished by the measuring instrument. We generate the pulse and hold waveform by a new technique where a voltage step with following linear voltage rise is applied to a bias capacitor. The frequency dependent damping is realized by an on-chip RC-environment fabricated with optical lithography. Josephson junction circuits are added on by means of e-beam lithography. Measurements show that switching currents can be detected with pulses as short as 5 ns and a resolution of 2.5% for a sample directly connected to the measurement leads of the cryostat. Detailed analysis of the switching currents in the RC-environment show that pulses with a duration of 20 us can be explained by a generalization of Kr, QC 20100924

Inelastic nuclear collisions of hadrons incident on silicon sensors can generate secondary highly ionising particles (HIPs) and deposit as much energy within the sensor bulk as several hundred minimum ionising particles. The large signals generated by these ‘HIP events’ can momentarily saturate the APV25 front-end readout chip for the silicon strip tracker (SST) sub-detector of the compact muon solenoid (CMS) experiment, resulting in deadtime in the detector readout system. This paper presents studies of this phenomenon through simulation, laboratory measurements and dedicated beam tests. A proposed change to a front-end component to reduce the APV25 sensitivity to HIP events is also examined. The results are used to infer the expected effect on the performance of the CMS SST at the future large hadron collider. The induced inefficiencies are at the percent level and will have a negligible effect on the physics performance of the SST.

The prototype of a fast beam chopper for hard X-rays, with a continuously variable duty cycle from less than 10 to more than 90% has been successfully developed, built and tested. The apparatus consists in 12 planetary stainless-steel blades that are 100 mm wide and are mounted on two large discs. All blades are kept permanently parallel to each other, thanks to a gear system, which also allows changing their orientation. The two main parameters of the chopper (duty cycle and chopping frequency) are controlled independently and remotely. In the present design, the device allows chopping frequencies ranging from 0 to 300 Hz. The principle of operation, preliminary results of the instrument's performance and an example demonstrating the capacity of the system for image quality improvement and X-ray dose reduction at the specimen are presented.

QC 20100525

Over the past decade the field of micro-electro-mechanical systems (MEMS) has attracted increased interest. Miniaturization of mechanical systems promise new directions in the progress of science and technology., Briefing charts only.

The need for a component capable of simulating semi-permanent changes in biological neurons, suitable for inclusion in brain models, and in perceptrons in particular, is discussed. Various devices intended for this purpose are reviewedAND EVALUATED. A novel method of flux integration, using a permalloy wire as the flux storing medium, and the voltage induced in a search coil as the result of magnetostriction in the wire for readout, is described in detail. The design procedure for the complete memory of an audio-perceptron, Tobermory, based on the magnetostrictive readout integrator, is oulined. Modifications in the integrator, intended to render it suitable for larger and topologically more sophisticated models, are anticipated. (Author)