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A superconductor exhibiting a polarity-dependent critical current is of fundamental as well as technological interest, because the superconducting (SC) layer can then admit a perfect dissipationless transmission along one direction while offering a large resistance along the opposite, leading to a phenomenon called SC diode effect or rectification. Here we demonstrate that SC diode effects are ubiquitous in superconductors and observable in a large variety of settings. Controllable via an out-of-plane magnetic field, we observe an extremely sensitive SC diode effect (type A) in superconducting vanadium or niobium stripes with symmetry breaking between their two edges. Nonreciprocity of critical current results from an out-of-plane field as small as 1 Oe, while the diode efficiency and polarity are manipulated via the strength and direction of the field. With the out-of-plane field carefully eliminated, an in-plane field also creates a sizeable asymmetry between critical currents (type B), regardless of whether this field is perpendicular or parallel to the current flow direction. Finally, we demonstrate nonreciprocal critical currents with a giant diode efficiency reaching 65% when the SC V film couples to a ferromagnetic EuS layer with in-plane magnetization orthogonal to current flow (type C) and a clear diode rectification is seen. This is also realized at zero applied field, in the remnant magnetic state of EuS. Our observations show the ubiquity of the superconducting diode effect, and pave the way for the development of versatile SC rectifiers employing simple structures using widely available materials.

This paper analyzes the properties of commercial silicon PIN photodiodes BPW34 as direct $\gamma$ -radiation sensors. Sample is formed by four photodiodes connected in parallel and polarized reversely. Current to voltage conversion and amplification is performed using a prototype circuit with a low noise transimpedance (TIA) operational amplifier with input current range of 1 nA - $3.3 \mu \mathrm{A}$ . The voltage characteristic from the amplifier circuit and induced current characteristic is measured by source measuring unit (SMU) Keithley 2636A for the same irradiation dose rates. Sample is irradiated for 140 s using a 60Co $\gamma$ -ray source. Obtained results have shown very good linearity between amplification circuit output voltage and induced photocurrent measured with SMU Keithley 2636A for dose rates ranging from 2.5 Gy/h to 11 Gy/h. Using voltage to current conversion formula, amplification of circuit input current is calculated and compared to induced photo current measured with SMU. These results show amplification circuit current error offset. Also, non-linearity results are shown for photo current under 1 nA. Due to offset error, but good linearity response, an output voltage vs. radiation dose calibration curve is given.

Josephson junctions (JJs), where both time-reversal and inversion symmetry are broken, exhibit a phase shift φ0 in their current-phase relation. This allows for an anomalous supercurrent to flow in the junction even in the absence of a phase bias between the superconductors. We show that a finite phase shift also manifests in the so-called Andreev interferometers—a device that consists of a mesoscopic conductor coupled to the φ0 junction. Due to the proximity effect, the resistance of this conductor is phase sensitive—it oscillates by varying the phase of the JJ. As a result, the quasiparticle current Iqp flowing through the conductor has an anomalous component, which exists only at finite φ0. Thus, the Andreev interferometry could be used to probe the φ0 effect. We consider two realizations of the φ0 junction and calculate Iqp in the interferometer: a superconducting structure with spin-orbit coupling and a system of spin-split superconductors with spin-polarized tunneling barriers., This work was partially funded by the Spanish Ministerio de Ciencia, Innovación y Universidades (MICINN) through Projects No. FIS2017-82804-P and No. PID2020-114252GBI00 (SPIRIT), and EU’s Horizon 2020 research and innovation program under Grant Agreement No. 800923 (SUPERTED). A.H. acknowledges funding by the University of the Basque Country (Project No. PIF20/05).

The effect of X-rays on the p-channel power vertical double diffused metal-oxide-semiconductor field-effect transistors (VDMOSFETs) was investigated. The VDMOSFETs were irradiated without gate polarization using three different Xray beams. Due to the polyenergetic nature of X-rays, their effect is much more complex than the effect of gamma radiation on transistors. The influence of X-rays on threshold voltage shift $(\Delta V_{T})$ and on the creation of fixed traps (FTs) in gate oxide and on switching traps (STs) near and at oxide/semiconductor interface was analyzed. The effect of STs on $\Delta V_{T}$ is more significant than in the case of y-radiation. The obtained results showed that the sensitivity to radiation depends on the radiation energy, and they are in accordance with the theoretical predictions.

This work was supported in part by the European Union's Horizon 2020 research and innovation programme under grant agreement No. 857558, and the Ministry of Education, Science and Technological Development of the Republic of Serbia, under the project No. 43011., The RADiation sensitive metal-oxide-semiconductor field-effect-transistors (RADFETs) were irradiated with gamma rays up to absorbed dose of 110 Gy(H2O). The results of threshold voltage, V-T , during irradiation with various positive gate biases showed the increase in V-T with gate bias. The threshold voltage shift, Delta V-T , during irradiation was fitted very well. The contributions of both the fixed traps (FTs) and switching traps (STs) during radiation on Delta V-T were analyzed. The results show the significantly higher contribution of FTs than STs. A function that describes the dependence of threshold voltage shift and its components on gate bias was proposed, which fitted the experimental values very well. The annealing at the room temperature without gate bias of irradiated RADFETs was investigated. The recovery of threshold voltage, known as fading, slightly increase with the gate bias applied during radiation. The Delta V-T shows the same changes as the threshold voltage component due to fixed states, Delta V-ft , while there is no change in the threshold voltage component due to switching traps, Delta V-st ., European Union's Horizon 2020 research and innovation programme 857558, Ministry of Education, Science & Technological Development, Serbia 43011

We present RESCURE, a security solution built on software, which retrofits Internet of Things (IoT) devices to secure ones. RESCURE exploits the entropy originating from the random variations of silicon (transistors) during manufacturing and generates a unique unforgeable root key and an identity per device. In this way, root key and identity are inseparable from the IoT hardware. To achieve lifetime reliability (reproducibility) and security (randomness) for root key and identity, we apply error correcting and randomness amplification algorithms to the signals derived from silicon. RESCURE supports certificates which are able to prove the device identity and authenticity. RESCURE supports multiple keys derivation (private keys or private/public key pairs) and End-to-End security. In this way an IoT device is able to communicate securely and independently with multiple actors (e.g., Service Providers). It supports secure storage so it is able to encrypt sensitive data such as application keys, sensitive data or software Intellectual Properties (IP). Finally, the entire device software is protected by secure boot and secure software update mechanisms allowing for malware-free software execution and renewable security and features. RESCURE has been prototyped on an ST32L4 device and its performance is presented across real use case scenarios covering the entire life cycle of the device. It is a low-cost solution for all the devices manufacturers that want to achieve high standard security without redesigning the hardware of their IoT product.

Low-cost interconnected devices, so-called Internet-of-Things (IoT), commonly have no dedicated or posses insufficient hardware security features. This is challenging, as IoT devices are becoming an integral part of critical infrastructures providing much needed additional functionality but also creating a significant security threat to the infrastructure. Due to the scale of IoT integration in critical infrastructures, a key issue in initial deployment and replacing of the devices is often the cost. RESCURE delivers a low-cost IoT security solution based on unique hardware anchors. More precisely, we are using PUFs (Physical Unclonable Function) technology based on SRAM (Static Random-Access Memory), which provides a unique and unclonable identifier as well as a root key for each device. As SRAM-PUFs-based approaches require no additional specialized hardware, it also presents a viable approach of retrofitting existing embedded devices already used.

This paper describes the possibility of using an Electrically Programmable Analog Device (EPAD) as a gamma radiation sensor. Zero-biased EPAD has the lowest fading and the highest sensitivity in the 300 Gy dose range. Dynamic bias of the control gate during irradiation was presented for the first time, this method achieved higher sensitivity compared to static-biased EPADs and better linear dependence. Due to the degradation of the transfer characteristics of EPAD during irradiation, a function of the safe operation area has been found that determines the maximum voltage at the control gate for the desired dose, which will not lead to degradation of the transistor. Using an energy band diagram, it was explained why the zero-biased EPAD has higher sensitivity than the static-biased EPAD.

The Eilenberger equation is a standard tool in the description of superconductors with an arbitrary degree of disorder. It can be generalized to systems with linear-in-momentum spin-orbit coupling (SOC), by exploiting the analogy of SOC with a non-Abelian background field. Such a field mixes singlet and triplet components and yields the rich physics of magnetoelectric phenomena. In this work we show that the application of this equation extends further, beyond superconductivity. In the normal state, the linearized Eilenberger equation describes the coupled spin-charge dynamics. Moreover, its resolvent corresponds to the so-called Cooperons, and can be used to calculate the weak-localization corrections. Specifically, we show how to solve this equation for any source term and provide a closed-form solution for the case of Rashba SOC. We use this solution to address several problems of interest for spintronics and superconductivity. First, we study spin injection from ferromagnetic electrodes in the normal state, and describe the spatial evolution of spin density in the sample, and the complete crossover from the diffusive to the ballistic limit. Second, we address the so-called superconducting Edelstein effect, and generalize the previously known results to arbitrary disorder. Third, we study weak-localization correction beyond the diffusive limit, which can be a valuable tool in experimental characterization of materials with very strong SOC. We also address the so-called pure gauge case where the persistent spin helices form. Our work establishes the linearized Eilenberger equation as a powerful and a very versatile method for the study of materials with spin-orbit coupling, which often provides a simpler and more intuitive picture compared to alternative methods., We acknowledge funding from Spanish Ministerio de Ciencia, Innovación y Universidades (MICINN) (Projects No. FIS2016-79464-P and No. FIS2017-82804- P). I.V.T. acknowledges support by Grupos Consolidados UPV/EHU del Gobierno Vasco (Grant No. IT1249-19). S.I. and F.S.B acknowledge funding from EUs Horizon 2020 research and innovation program under Grant Agreement No. 800923 (SUPERTED).

Ferromagnetic insulators (FI) can induce a strong exchange field in an adjacent superconductor (S) via the magnetic proximity effect. This manifests as spin splitting of the BCS density of states of the superconductor, an important ingredient for numerous superconducting spintronics applications and the realization of Majorana fermions. A crucial parameter that determines the magnitude of the induced spin splitting in FI/S bilayers is the thickness of the S layer d: In very thin samples, the superconductivity is suppressed by the strong magnetism. By contrast, in very thick samples, the spin splitting is absent at distances away from the interface. In this work, we calculate the density of states and critical exchange field of FI/S bilayers of arbitrary thickness. From here, we determine the range of parameters of interest for applications, where the exchange field and superconductivity coexist. We show that for d>3.0ξs, the paramagnetic phase transition is always of the second order, in contrast to the first-order transition in thinner samples at low temperatures. Here ξs is the superconducting coherence length. Finally, we compare our theory with the tunneling spectroscopy measurements in several EuS/Al/AlOx/Al samples. If the Al film in contact with the EuS is thinner than a certain critical value, we do not observe superconductivity, whereas, in thicker samples, we find evidence of a first-order phase transition induced by an external field. The complete transition is preceded by a regime in which normal and superconducting regions coexist. We attribute this mixed phase to inhomogeneities of the Al film thickness and the presence of superparamagnetic grains at the EuS/Al interface with different switching fields. The steplike evolution of the tunnel-barrier magnetoresistance supports this assumption. Our results demonstrate on the one hand, the important role of the S layer thickness, which is particularly relevant for the fabrication of high-quality samples suitable for applications. On the other hand, the agreement between theory and experiment demonstrates the accuracy of our theory, which, originally developed for homogeneous situations, is generalized to highly inhomogeneous systems., F.S.B. acknowledges funding by the Spanish Ministerio de Ciencia, Innovación y Universidades (MICINN) (Project FIS2017-82804-P). T.T.H. acknowledges funding from the Academy of Finland (Project number 317118). A.H. acknowledges funding by the Department of Education of the Basque Government (Ikasiker grant). C.G.-O. acknowledges funding of the Ph.D. fellowship from MPC foundation. S.K. acknowledges for the fellowship of the ICTP Program for Training and Research in Italian laboratories, Trieste, Italy. C.R. acknowledges support from Gobierno Vasco (Grant No. IT 1255-19). F.G. acknowledges the European Research Council under the EU’s Horizon 2020 Grant Agreement No. 899315-TERASEC for partial financial support. We acknowledge funding from EU’s Horizon 2020 research and innovation program under Grant Agreement No. 800923 (SUPERTED).

Measurement of absorbed dose and dose rate is a common task in radiation environments such as space. This is accomplished with the specialized instruments known as radiation dosimeters. Among the most commonly used radiation dosimeters in space missions are those based on the Radiation Sensitive Field Effect Transistors (RADFETs). In this paper, we propose a design concept for a radiation hardened readout system for the real-time measurement of absorbed dose and dose rate with RADFET. The successive switching between the absorbed dose and dose rate readout modes, as well as the subsequent data processing, are performed by the self-adaptive fault-tolerant Multiprocessing System-on-Chip (MPSoC). The integrated framework controller and the real-time monitoring of particle flux with the embedded Static Random Access Memory (SRAM) enable the autonomous selection of operating and fault-tolerant modes, thus achieving the optimal performance under variable radiation conditions.

As the number of so-called Internet-of-Things is continuously rising and the urge for regular hardware updates has never been higher, the security of our smart objects all around us is often skipped due to lack of development time. By default, these devices are equipped with a primitive bootloader, which is executing code located at a designated address. Within this document, we are describing a simple but worthwhile validation mechanism, which is realized by using digital signature algorithm included in the bootloader. As a result, we are making sure that no malicious code or malware can be executed and the running application is originating from a trusted and known developer. Nevertheless, even the strongest cryptographic system cannot ensure the highest possible security, if the device itself is prone to fault injection attacks. A simple alteration of the voltage or clock speed is sufficient in order to unsettle the device's usual and intended behaviour and cause instruction skipping among others. At worst, this could result in bypassing of authentication mechanisms, one of the most common targets of an attack. With the aid of randomly-chosen delays in instruction processing as well as multiple use of authentication mechanisms, we are describing straightforward mechanisms in order to decrease the level of success of common fault injections. Moreover, a list of recommendations is given in this document suitable for situations, where resources are limited and no additional hardware can be added., This work was partially supported by the Eurostars-2 joint programme with co-funding from the European Union Horizon 2020 research and innovation programme under the grant agreement E11897 RESCURE "Retrofit Security for Critical infrastructures". Furthermore, this work was also partially supported by the Austrian Ministry for Transport, Innovation and Technology under the framework of "IKT der Zukunft" with the FFG grant agreement project 865233.

Truth, problems, research In his search for the truth, every history researcher often encounters the difficulties of methodological nature. A very complex path, which is, in case of history researchers, more difficult and complicated, due to a number of obstacles, leads to a discovery of truth. However, what exactly is the truth and how much do we need it nowadays, who wants it and is there a desire to discover the truth? These questions are not easy to answer. What are we faced with and what are the most common problems in the research of the history of physical culture? What makes us make omissions, errors and mistakes? 1. Hasting and hurrying to complete the papers, when we, often faced with short deadlines, fail to meet all methodological requirements. 2. Using the information from the papers by other authors is taken for granted, without adequate verification, assuming their reliability, and if the information is inaccurate, it results in multiplying inaccurate information which thus becomes an inaccurate secondary source to the next researcher. 3. In our research we are sometimes unable to distance ourselves from our nation, religion and politics and we therefore tend to overestimate the achievements by our own people. 4. We do not always pay enough attention to or we neglect or do not consider the economic, political, historical, cultural and other conditions under which an event occurred as well as their interrelations and their impact on the studied issue. 5. In research we often exclude comparative studies on the development and achievements of European countries and Serbia in all aspects of political, economic and cultural life. 6. Professional and scientific papers' review is easily accepted and taken for granted since, due to the authors' deadlines, we are often under pressure and forced to assess the suggested work without thorough and adequate consideration. For the aforesaid reasons, we therefore advocate a more cautious and more serious approach to the research of the past in order to avoid mistakes and inaccuracies.

Dye-sensitized solar cells are the closest mankind has come to replicating nature?s photosynthesis. The type of a dye influences the efficiency of these cells. In this paper we studied curcumin dye as a sensitizer in dye-sensitized solar cells and compared it with most often used cyanidin. The results have shown that curcumin has higher efficiency and higher absorption in the visible part of the spectrum compared to cyanidin. Simulation models of dye molecules, curcumin and cyanidin, are deprotonated upon adsorption on the titanium dioxide surface. The energy levels obtained from the calculation indicate a higher probability of electron transition from molecule to titanium dioxide surface in case of curcumin than in case of cyanidin. Based on these results, we concluded that curcumin dye has better properties as sensitizer in dye-sensitized solar cells.

We calculate the interference correction to the conductivity of doped transition metal dichalcogenide (TMDC) monolayers. Because of the interplay between valley structure and intrinsic spin-orbit coupling (SOC), these materials exhibit a rich weak localization (WL) behavior that is qualitatively different from conventional metals or similar two-dimensional materials such as graphene. Our results can also be used to describe graphene/TMDC heterostructures, where the SOC is induced in the graphene sheet. We discuss new parameter regimes that go beyond existing theories, and can be used to interpret recent experiments in order to assess the strength of SOC and disorder. Furthermore, we show that an in-plane Zeeman field can be used to distinguish the contributions of different kinds of SOC to the WL magnetoconductance., 15 pages, 6 figures

We calculate the effect of impurities on the superconducting phase diagram of transition metal dichalcogenide monolayers in the presence of an in-plane magnetic field. Due to strong intrinsic spin-orbit coupling, the upper critical field greatly surpasses the Pauli limit at low temperatures. We find that it is insensitive to intravalley scattering and, ultimately, limited by intervalley scattering., Comment: 10 pages, 8 figures

Spin-split superconductors exhibit an electron-hole asymmetric spin-resolved density of states, but the symmetry is restored upon averaging over spin. On the other hand, asymmetry appears again in tunneling junctions of spin-split superconductors with a spin-polarized barrier. As demonstrated recently in both theory and experiment, this fact leads to a particularly strong thermoelectric effect in superconductor-ferromagnet structures. In this work we show another important effect stemming from the electron-hole asymmetry: current rectification. We calculate the charge current in spin-polarized tunnel junctions of a normal metal and a spin-split superconductor with ac and dc voltage bias. In the dc case, the I-V curve is not fully antisymmetric and has a voltage-symmetric component due to spin polarization. This translates to the existence of a rectified current in the ac case, which is proportional to the spin polarization of the junction and strongly depends on the frequency of the applied bias. We discuss possible applications of the rectification effect, including a diode for superconducting electronics and radiation detectors. The analysis of the rectified charge current is supplemented by the discussion of heat current and relevant noise correlators, where electron-hole asymmetry also plays an important role, and which are useful for applications in detectors., This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 800923 (SUPERTED). It was also supported by the Academy of Finland (project number 317118), and the Spanish Ministerio de Ciencia e Innovación through project PID2020-114252GB-I00 (SPIRIT).