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Quantum-dot Cellular Automata (QCA) has become one of the promising studies for nano-scale computing. QCA is one of the candidate technologies to be replaced with CMOS technology. QCA technology not only reduces power consumption and delay but also increases operating frequency and speed. The arithmetic logic unit is the essential component in a processor that performs arithmetic and logical operations. This paper presents a novel 5 × 5 reversible logic gate called the NRRG (Norouzi_Rasouli Reversible Gate) which can be used as the basic building block of 4:1 and 8:1 reversible multiplexers. Then, we have designed a RALU (reversible arithmetic and logic unit) using this gate. Our design can perform 20 operations such as AND, NAND, OR, XOR, XNOR, COPY, addition, and increment. The proposed QCA RALU requires 0.44 μm2 area, 480 QCA cells, and 10 clock phases. The proposed design needs less cell count, delay, and cost of QCA compared to previous works. The structure is implemented without any rotated cells and only uses one layer which improves the manufacturability of the design. The architectures are designed and simulated using QCA Designer 2.0.3. [ABSTRACT FROM AUTHOR]

Programmable and non-volatile spin-based logic devices have attracted significant interest for use in logic circuits. Realization of logic operations via spin–orbit torque (SOT) driven magnetization switching could be a crucial step in the direction of building logic-in-memory architectures. In this work, we demonstrate experimentally, the realization of four logic operations in a heavy metal/ferrimagnet bilayer structure via SOT switching. We also propose a general scheme for choosing input parameters to achieve programmable logic operations. The bulk and tunable perpendicular magnetic anisotropy and relatively lower saturation magnetization in ferrimagnets are found to make them more energy efficient in performing logic operations, as compared to conventional ferromagnets. Thus, ferrimagnets are promising candidates for use in logic-in-memory architectures, leading to the realization of user-friendly spin logic devices in the future. [ABSTRACT FROM AUTHOR]

As one of the most successful platforms of quantum control, trapped ions can be modulated by sequential microwave pulses to realize high-fidelity quantum logic gates, and dephasing noise may lead to invalidation of phase locking. In this work, we utilize the Dirac–Frenkel time-dependent variational approach with Davydov ansatz to simulate spin echo dynamics in the framework of spin-boson model. As the essential modulation parameters, pulse duration and waiting time have been comprehensively investigated to optimize the phase gates by two microwave pulses. We find that, as spin orientation undergoes periodic changes, the phase difference by acting one and two pulses exhibits spontaneous locking following time evolution, which indicates the robustness of the quantum phase gates. Spectrum of the environmental noise that is appropriate for the phase locking is also determined. [ABSTRACT FROM AUTHOR]

The reversible quantum-flux-parametron (RQFP) is a reversible logic gate based on an energy-efficient superconductor logic family, namely, the adiabatic quantum-flux-parametron logic. The RQFP can perform logic operations in a thermodynamically reversible manner (i.e., without energy dissipation) in the quasi-static limit due to its logical and physical reversibility. Hence, it can be used for investigating the fundamental relations between information and thermodynamics from a circuit perspective. In the present study, we propose a reversible flip-flop (RFF) comprising an RQFP and investigate the minimum energy dissipation required for general information processing through numerical simulation using an RFF-based circuit. This circuit includes fundamental information processing (combinational logic, sequential logic, and data erasure) and can, thus, be used as a physical model for such an investigation. The numerical simulation of this circuit shows that both combinational and sequential logic operations can be conducted without energy dissipation in the quasi-static limit and that the amount of erased data determines the minimum energy dissipation. These results indicate that general information processing can be conducted in a thermodynamically reversible manner by using RQFP circuits as long as all data, including garbage outputs, are conserved. [ABSTRACT FROM AUTHOR]

A numerical model for a spin wave delay-line active ring resonator is presented. Spin wave dynamics along a one-dimensional strip of magnetic material are modeled using the nonlinear Schrödinger equation. The equation is solved numerically in Fourier space using the fourth-order Runge–Kutta method and yields qualitative agreement with experimental measurements of spin wave dynamics in two different regimes. The model provides a useful tool for performing experiments based on neuromorphic computing and logic gates in traveling spin wave devices. [ABSTRACT FROM AUTHOR]

The recent progress in quantum computing and space exploration led to a surge in interest in cryogenic electronics. Superconducting devices such as Josephson junction, Josephson field effect transistor, cryotron, and superconducting quantum interference device (SQUID) are traditionally used to build cryogenic logic gates. However, due to the superconducting nature, gate-voltage-based control of these devices is extremely difficult. Even more challenging is to cascade the logic gates because most of these devices require current bias for their operation. Therefore, these devices are not as convenient as the semiconducting transistors to design logic gates. Here, to overcome these challenges, we propose a ferroelectric SQUID (FeSQUID) based voltage-controlled logic gates. FeSQUID exhibits two different critical current levels for two different voltage-switchable polarization states of the ferroelectric. We utilize the polarization-dependent (hence, voltage-controllable) superconducting to resistive switching of FeSQUID to design Boolean logic gates such as Copy, NOT, AND, and OR gates. The operations of these gates are verified using a Verilog-A-based compact model of FeSQUID. Finally, to demonstrate the fanning out capability of FeSQUID-based logic family, we simulate a two-input XOR gate using FeSQUID-based NOT, AND, and OR gates. Together with the ongoing progress on FeSQUID-based non-volatile memory, our designed FeSQUID-based logic family will enable all FeSQUID-based cryogenic computer, ensuring minimum mismatch between logic and memory blocks in terms of speed, power consumption, and fabrication process. [ABSTRACT FROM AUTHOR]

A memristor is a two-terminal electrical component with the scope of future computing applications and analog electronics. In this report, bismuth sulfide decorated one-dimensional carbon nitride nanotube was synthesized and characterized with various analytical techniques. The electrical property of the synthesized material was measured using a two-terminal metal–insulator–metal type of device that exhibited the resistive switching characteristics with the ON to OFF ratio of 2 × 103. The electron transport mechanism of the device was followed by Schottky emission and Poole–Frenkel emission for a low conductance state and Ohmic conduction behavior at the high conductance state. A decrease in the trap depth was identified in the simulation study with increasing applied potential and that supported the proposed mechanism. Read endurance and retention behavior of the device are stable in nature, supported by the statistical analysis. Furthermore, a hybrid logic gate was designed using two identical memristors, one CMOS inverter, one resistor, one voltage divider, and a buffer gate. The designed logic gate exhibited stable nand and nor gate operation based on the control signal. [ABSTRACT FROM AUTHOR]

Many researchers have focused on molecular electronics, and this field can progress faster by applying semiconductors to molecular modeling. In this work, two middle rings of a bipyridine–biborinine molecular diode are rotated from 25∘ to 90∘ such that the current along the molecule is reduced. The current is minimum and almost zero at 90∘, while it is maximum at 25∘. Accordingly, considering these two angles, the molecule can act as a switching device when the two middle rings are rotated. The bipyridine–biborinine molecular diode is modeled considering the effect of rotation by including two resistors in the model. Two parallel diodes are used in this modeling for pyridine and borinine rings. The ideality factors of these diodes are varied based on the electronegativity of pyridine and borinine rings. This model is then applied to consider different molecular logic gates such as NAND, NOR, NOT, OR and AND gates, as well as molecular logic circuits (half adder and full adder), using the unique capabilities of the LTspice software. [ABSTRACT FROM AUTHOR]

Circularly polarized long afterglow (CPLA) attracts great interests in multi‐disciplinary fields with significant potentials in optical multiplexing applications, but achieving full‐color and white CPLA is still challenging. The present contribution reports the first success in utilizing circularly polarized phosphorescence energy transfer (CPP‐ET) combined with chirality‐selective absorption (CSA) to construct full‐color and white CPLA materials. Blue CPLA with luminescence dissymmetry factor (glum) of 3×10−2 is firstly obtained via the CSA effect of chiral helical polyacetylene and blue ultralong afterglow of inorganic phosphor BP. Significantly, full‐color and white CPLA films are prepared by simply blending different fluorophores into the blue‐CPLA films via CPP‐ET. Benefited from the persistent luminescence of BP, the lifetimes of the fluorophores increase from nanoseconds to minutes, and ultralong full‐color CPLA emissions lasting for more than 20 min are realized with glum of 10−3. Also noticeably, chiral optoelectronic devices, multi‐dimension information encryption and chiral logic gate are developed based on the full‐color tunable CPLA‐active materials. The established strategy provides a universal platform for future development of CPLA‐active materials with great applications. [ABSTRACT FROM AUTHOR]

The increasing demand of integration density improvement and battery-powered device efficiency reduced complementary metal-oxide semiconductor (CMOS) technology node. In the technology of CMOS, the components are mainly affected with leakage power, dynamic switching power, short circuit power, gate oxide tunneling leakage current, sub threshold leakage current, and so on. To reduce the above limitations, design of high efficient low power static logic circuit using shorted-gate (SG) fin field-effect transistor (FinFET) based INput DEPendent (INDEP) in 22 nm CMOS technology (SLC-SG-FinFET-INDEP-22 nm CMOS) approach is proposed in this manuscript. The better selection of inputs to proposed INDEP FinFETs model is used for reducing leakage power. The efficiency of the proposed SLC-SG-FinFET-INDEP-22 nm CMOS technique is analysed using delay, power, power delay product, and stability analysis using noise margin. Thus, the proposed SLC-SG-FinFET-INDEP-22 nm CMOS has attained 21.31%, 41.47% and 12.7% lower delay, 20.87%, 34.5% and 22.41% lower power and 4.5%, 25.7% and 32.11% higher speed than existing methods static logic circuit input-controlled leakage restrainer transistor in 22 nm CMOS (SLC-ICLRT-22 nm CMOS), static logic circuit using self-control leakage-suppression block in 22 nm CMOS technology (SLC-SCLSB-22 nm CMOS), and static logic circuit using computational digital low dropout in 22 nm CMOS technology (SLC-CDLDO-22 nm CMOS) methods, respectively. [ABSTRACT FROM AUTHOR]

The paper reports simple yet effective circuits for realizing XOR and XNOR logic operations with polarity, each employing a single current conveyor. The proposed polar logic circuits require four MOS switches and two resistors, besides a single CCII+ (second generation current conveyor), in each case. The new proposed circuits are simulated using 0.18 µm CMOS process parameters with a ± 1.8 V supply voltage and reference DC voltage of 1 V, thus enabling polar logic outputs. The polar output for logic 0 and 1 is in form of − 1 V and + 1 V respectively. The results included in support of the work are promising for future applications of the proposal in design of communication circuits. To facilitate better integration prospects, the proposed circuits are further simplified by removing one of the two used resistors and replacing CCII by CCCII (current controlled current conveyor). The simplified polar XOR gate is also verified through simulations. System design applications are expected to evolve from proposed work. The new proposed circuits are expected to significantly contribute to the advancement of circuit design. [ABSTRACT FROM AUTHOR]

Ambipolar organic electrochemical transistors (OECTs) with a single organic mixed ionic‐electronic conductor (OMIEC) have unique advantages by reducing fabrication complexity and cost in complementary logic circuit and bioelectronic applications. However, the design and synthesis of high‐performance ambipolar OMIECs for efficient transport and coupling both cation/anion and electron/hole remain challenging. Herein, a donor–acceptor (D–A)‐typed ambipolar OMIEC polymer (DHF‐gTT) is presented, whose superior ambipolarity stems from the concurrent oligoethyleneglycol‐functionalized D/A units that facilitates cation/anion injection and transport. Additionally, the fluorination of acceptor unit improves both hole/electron transports due to the fully‐locked backbone and promotes electron injection by down‐shifting molecular energy levels. Consequently, DHF‐gTT‐based OECTs achieve balanced figure‐of‐merit (µC*) for both p‐type and n‐type operations (12.4–14.6 F cm−1 V−1 s−1), setting new benchmarks for ambipolar OECTs, in terms of n‐type µC* and electron/hole mobilities. Such ambipolar OECTs enable the inverter to achieve a record‐high gain (102 V/V) and associated n‐type and p‐type molecular detectors to offer real‐time and highly sensitive detection of histamine and hydrogen peroxide detection, respectively. These results indicate the effectiveness of judicious molecular design on achieving high‐performance ambipolar OMIECs, allowing the state‐of‐the‐art single‐component ambipolar OECTs for both highly integrated logic circuit and bioelectronic applications. [ABSTRACT FROM AUTHOR]

All‐optical logic gates (AOLGs) have attracted considerable attention for their high computing speed, low power consumption, and parallel processing; however, chemical design of new luminescent materials is a challenge to explore a facile platform for undertaking AOLGs. Here, an AOLG system is developed based on the organic–inorganic hybrid halides [NH3(CH2)2NH3]2ZnCl6:Mn2+ with tricolor luminescence under dual‐wavelength excitation, and the intrinsic emission mechanisms are further addressed. When employing 275 and 365 nm UV excitations as input signals, the AOLGs conduct Boolean operations “OR, YES, AND” via identifying the green (G) and red (R) emissions and their intensity ratio (R/G) as output signals. This work further demonstrates the AOLG operation imaging and image processing via hybrid halide emitters, indicating promise in optical computing applications. [ABSTRACT FROM AUTHOR]

O-Vanillin derived Schiff base 1-[(E)-(2-hydroxy-3-methoxybenzylidene) amino]-4-methylthiosemicarbazone (VCOH) has been synthesized for colorimetric and fluorescence chemosensors towards PO43− ions. A fluorescence 'turn-on' sensing mechanism of VCOH towards PO43− ions has been explained due to emission from the VCO− ion formed upon transfer of the phenolic proton of VCOH to a PO43− ion. The 1 : 1 stoichiometry between the VCOH probe and PO43− ion is confirmed by Job's plot based on UV-vis titration. The limit of detection (LOD) of VCOH towards PO43− ions is found to be 0.49 nM. The PO43− ion sensing property of probe VCOH has been applied to prepare portable paper strips and for the analysis of real water samples. Fluorescence 'turn-on' and 'turn-off' responses of VCOH towards PO43−and H+ respectively have been used to construct a molecular logic gate. Fluorescence based sensing studies in which the concentration of analytes is adjusted over a broad range can be both laborious and expensive. In order to address these challenges, we have utilized various soft computing methods, including artificial neural networks (ANN), fuzzy logic (FL), and adaptive neuro-fuzzy inference systems (ANFIS), to appropriately model the 'turn-on' and 'turn-off' behaviors of the VCOH probe upon addition of PO43− and H+ respectively as well as to predict the experimental sensing data. [ABSTRACT FROM AUTHOR]

Mixed‐halide perovskites (MHPs) have emerged as important semiconductor materials for optoelectronic devices due to the bandgap tunability by halide composition. However, their device applications are hampered by light‐induced ion migration and halide segregation, leading to the formation of lower bandgap domains with red‐shifted photoluminescence. Previous studies of phase segregation in MHPs have predominantly focused on their linear optical properties. Herein, nonlinear absorption (NLA) properties of MAPbBr2I films before and after femtosecond laser irradiation are investigated using the Micro‐I‐scan technique. An unusual NLA switching from reverse‐saturable absorption (RSA) to saturable absorption (SA) under intense laser illumination is found. It is unveiled that the initial RSA originates from two‐photon absorption in uniform bromide‐rich regions of as‐prepared film whereas the SA occurs due to state filling effect in the newly generated low bandgap I‐rich phases under laser irradiation. The switching threshold and effective NLA coefficient are highly dependent on the distribution of halide ions, which is controllable through the laser illumination time. Furthermore, an all‐optical logic gate scheme is demonstrated based on the unusual NLA switching. The results not only unveil that halide segregation results in NLA switching in MHPs but also pave the way for the realization of MHPs‐based nonlinear photonic devices. [ABSTRACT FROM AUTHOR]

The main complexity classes of the Parameterized Intractability Theory are based on weighted Boolean circuit satisfiability problems and organized into a hierarchy so-called W-hierarchy. The W-hierarchy enables fine-grained complexity analyses of parameterized problems that are unlikely to belong to the FPT class. In this paper, we introduce the Th-hierarchy, a natural generalization of the W-hierarchy defined by unweighted threshold circuit satisfiability problems. Investigating the relationship between Th-hierarchy and W-hierarchy, we discuss the complexity of transforming Threshold circuits into Boolean circuits, and observe that sorting networks are powerful tools to handle such transformations. First, we show that these hierarchies collapse at the last level (W[P] = Th[P]). After that, we present a time complexity analysis of an AKS sorting network construction, which supports some of our results. Finally, we prove that Th[ t ] ⊆ W[SAT] for every t ∈ ℕ. As a by-product, our studies suggest that it is relevant to consider a new class based on logarithmic depth circuits in the W-hierarchy. [ABSTRACT FROM AUTHOR]

Cupric ions (Cu2+), pyrophosphate (PPi), and alkaline phosphatase (ALP) are involved in a variety of biochemical processes such as DNA replication, cellular metabolism and play an important role in human growth and development. It is of great significance to establish a method for the sensitive detection of Cu2+, PPi and ALP. In this work, polyethyleneimine-capped silver nanoclusters (PEI-AgNCs) were successfully synthesized by a one-pot method using hydrazine sulfate as reductant, exhibiting a unique strong fluorescence emission in the near-ultraviolet region at ∼339 nm. Since the fluorescence of PEI-AgNCs can be quenched by Cu2+ through inner filtering effect (IFE), then recovered by competitive binding of pyrophosphate and Cu2+, and later weakened again by catalytic hydrolysis of alkaline phosphatase, a sensitive and selective strategy based on the changes of fluorescence "ON" or "OFF" was established to detect Cu2+, PPi and ALP. The LODs of these three analytes were 36 nM, 0.2 μM, and 0.14 U L−1 at a S/N ratio of 3, respectively. A series of logic gate circuits for sensing cupric ions, pyrophosphate, and alkaline phosphatase were successfully constructed. The established methods have the potential for biosensing and environmental analysis and the specific UV-A fluorescence property of PEI-AgNCs may be helpful in photonic and optical areas. [ABSTRACT FROM AUTHOR]

As CMOS technology approaches its physical and technical limits, alternative technologies such as nanotechnology or quantum computing are needed to overcome the challenges of lithography, transistor scaling, interconnects, and miniaturization. This article introduces a novel nanotechnology that uses atomic-scale silicon dangling bonds (ASDB) to create high-performance, low-power, nanoscale logic circuits. DBs are atoms that can form basic logic gates on a silicon surface using a scanning tunneling microscope device. ASDB can also be an alternative to the existing complementary metal oxide semiconductor (CMOS) technology. The article also proposes a new bar-shaped pattern to design gates and logic circuits with ASDB nano tecnolgoy. The bar-shaped pattern improves the reliability of the output, reduces the area and power consumption, and solves the problem of interatomic energy effects of ASDB. The article demonstrates the efficiency of the bar-shaped pattern by implementing two-input gates such as AND, NAND, OR, NOR, XOR, XNOR, and a 2:1 multiplexer with ASDB. The article also uses a powerful tool called SiQAD to simulate and verify the performance of the proposed structures with ASDB. According to the simulation results, the proposed logic gates are more energy efficient, stable, and compact than the previous structures. They consume 35% and 24.34% less energy and have 14.18% more stability, respectively. [ABSTRACT FROM AUTHOR]

Inevitability to reduce the size, cost and complexity of multilevel inverter (MLI) to evolve simplified RSC (Reduced switch count) MLIs has created diversified effects such as limited switching redundancies which further restricted modularity and flexibility of implementing PWM schemes. Among the PWM schemes of RSC-MLIs, modified reduced carrier (MRC) PWM with unified switching logic (USL) is the simplest and claims to be superior with the state of art in terms of implementation, line harmonic performance, imposing least controller computational burden (of 6.5 µS to realise a three-phase seven-level RSC-MLI) by adapting minimal carrier constraints. However, this is valid for sophisticated digital controllers such as dSPACE MicroLabBox, but not for low-end cost-effective controllers such as dSPACE1104 (imposing a computational burden of nearly 25 µS to control a single-phase RSC-MLI). Thus, this paper proposes an improved USL which adopts no carrier constraints and operates with less computational burden over the conventional USL. The proposed USL gives flexibility to the user to implement a part of the switching logic with analogue circuits and thereby avoid the requirement of high-end digital controller. The scalability and superiority of the proposed USL is demonstrated for symmetrical and asymmetrical configurations of popular cascaded T-type RSC-MLI. Efficacy of the proposed USL is demonstrated with dSPACE 1104 controller and dSPACE FPGA R&D Micro-lab Box. [ABSTRACT FROM AUTHOR]

One of the major study areas in VLSI system design is the creation of an area-efficient, high-speed adder. So this paper focused on an effective adder design as an Area Effective Novel Sum Generator (AENSG) to make it suitable for real-time applications. The major operations involved in this adder are Brent Kung addition, group kill and generate (KG) signal generation, Kill Generate Propagate (KGP) signal generation, and various sum generation categories. In the sum-generating block, AENSG is utilized to minimize the space by a reduction in the number of logic gates. Xilinx ISE 13.1 is used to synthesize and validate the suggested adder design. The 64-bit AENSG adder has 37.98%, 9.09% lesser number of logic gates and 34.81%, 28.40% lesser delay when compared with PPF/CSSA_4 and hybrid adder respectively. [ABSTRACT FROM AUTHOR]

The advancement of bio‐ionotronics for the brain‐computer interaction necessitates an exploration of the mechanisms of electron‐ion coupled transport in solid state devices. In this study, a bio‐p–n junction composed of n‐type bacteriorhodopsin and p‐type P3HT are proposed. By leveraging electron‐proton synergistic effects, an opto‐ionotronic bio‐diode capable of performing ionotronic switching and rectification functions is fabricated. The switching behavior of the bio‐diode can be controlled both optically and electrically. Under light illumination, the ionotronic bio‐diode exhibits a rectification effect approaching that of an ideal diode, with a reliability of 99% and a rectification ratio of ≈661. Additionally, this bio‐organic composite ionotronic bio‐diode exhibits wide pH responsiveness, good photostability, and high biocompatibility. The proposed opto‐ionotronic bio‐diode can be utilized as a fundamental component in logic circuits, bridging the gap between semiconductor technology and biological systems, and represents a novel paradigm for the advancement of brain‐computer interaction. [ABSTRACT FROM AUTHOR]

Inspired by the human brain's capacity as a powerful biological computer capable of simultaneously processing a vast array of cognitive tasks, many emerging artificial synapse devices have been developed in recent years. Electric-double-layer (EDL) transistors based on interfacial ion-modulation have attracted widespread attention for simulating synaptic plasticity and neural functions. Here, low-voltage EDL p-type thin-film transistors (TFTs) are fabricated on glass substrates, with Ni-doped cuprous iodide (Ni0.06Cu0.94I) as the channel and chitosan as the dielectric. The electrical performance of the Ni0.06Cu0.94I TFTs is investigated: current on/off ratio of 6.4 × 104, subthreshold swing of 33 mV/dec, threshold voltage of 1.38 V, operating voltage of 2 V, and saturation field-effect mobility of 15.75 cm2 V−1 s−1. A dual in-plane gate OR logic operation is demonstrated. Importantly, by applying single voltage pulses, dual voltage pulses, and multiple voltage pulses to the gate, the Ni0.06Cu0.94I transistors exhibited typical synaptic characteristics, including short-term potentiation, short-term depression, long-term potentiation, long-term depression, paired-pulse facilitation, and spiking-rate-dependent plasticity. Furthermore, the synaptic transistor can also simulate the learning–forgetting–relearning process of the human brain. These remarkable behaviors of voltage-stimulated synaptic transistors have potential for neuromorphic applications in future artificial systems. [ABSTRACT FROM AUTHOR]

Through precise band engineering, Van der Waals heterostructures integration holds great promise for advancing high‐performance optoelectronic devices, especially photodetectors. This study presents self‐sustaining, dual‐polarity, high photo‐responsive heterostrutures (HS) photodetectors based on Sb2Se3, specifically Bi2Se3/Sb2Se3 and ZnSe/Sb2Se3. The Bi2Se3 (ZnSe) layer functions as a channel in a reconfigurable HS phototransistor configuration. These HS devices demonstrate a negative photoconductive response with bias‐modulated polarity switching of the photocurrent. The Bi2Se3/Sb2Se3 device exhibits a responsivity switch from −4 mA W−1 to 0.14 A W−1, while the ZnSe/Sb2Se3 device shows a substantially enhanced responsivity switch from ‐400 mA W−1 to 12 A W−1. This negative photo response results from a photoinduced carrier trapping mechanism at the interface of the channel layer and photosensitizer material. The bias modulation enables the switching from negative to positive responsivity. A comprehensive investigation of photoconductivity modulation provides a deeper understanding of the impact of the photogating effect and trap states under applied bias conditions. Ultrafast transient spectroscopy supports these findings, offering insights into the dynamics of charge carrier relaxation mechanisms and the trapping of photoexcited carriers in defect states, crucial for explaining the dual polarity photo response. These devices present significant advantages for switchable light imaging, optical communication, memory devices, convolution processing, and logic circuits. [ABSTRACT FROM AUTHOR]

The interfacial Dzyaloshinskii–Moriya interaction (DMI) acting as an essential source to stabilize spin textures in ferromagnetic ultrathin films has revealed its significant role in spin–orbit torque (SOT)-driven magnetic switching. Based on a convincing homochiral Néel domain wall model, the in-plane (IP) magnetic field associated with the DMI effect has been confirmed as an essential prerequisite for deterministic SOT-driven switching. Although the presence of the IP field is required, the impact of IP field magnitude combined with the DMI effect on SOT-driven switching in different heavy metals (HMs) has never been considered together. In this research, SOT-induced switching under various IP fields in Pt, W, or Ta/CoFeB/MgO systems has been studied. The results show that the critical threshold current IC is almost independent of the IP field in the Pt-based structure; however, it significantly decreases with an increase in the IP field in the W- and Ta-based systems. Combining the derived DMI field and the magnetic domain nucleation, it is concluded that the significant difference in DMI fields and the domains' nucleating positions are the main reasons for the above phenomenon. Exploiting the distinct dependent properties of IC on the IP field, a six resistance state multilevel storage and five programmable spin logic gates are proposed and realized. This study provides insight into the special ability of the SOT effect modulated by the DMI, and also expands an effective way to construct spin-based devices based on this unique spintronic effect. [ABSTRACT FROM AUTHOR]

Direct printing of conjugated polymer thin‐film transistors enables the fabrication of deformable devices with low cost, high throughput, and large area. However, a relatively poor device performance of printed devices remains a major obstacle to their application in high‐end display backplanes and integrated circuits. In this study, high‐performance and highly stackable printed organic transistors is developed, arrays, and circuits using a near‐amorphous polymer, indacenodithiophene‐co‐benzothiadiazole (IDT‐BT). The printed devices exhibited high saturation mobility (>1 cm2 V−1 s−1), high on/off ratio (>107), and low subthreshold slope (245 mV dec−1). In addition, 16 × 16 printed IDT‐BT arrays achieved 100% fabrication yield, with excellent device‐to‐device uniformity and low variations of mobility (9.55%) and threshold voltage (4.51%), and good operational and environmental stability (>365 days). Furthermore, five stacked 3D transistors are demonstrated with an excellent 3D uniformity without compromising device performance due to a low required thermal budget for processing amorphous IDT‐BT. Finally, a new concept of 3D universal logic gate with high voltage gain (33.91 V/V) and record density (100 printed transistors per cm2) is proposed and fabricated, which is relevant for the commercialization of low‐cost printed display backplanes and high‐density integrated circuits based on highly processable polymeric semiconductors. [ABSTRACT FROM AUTHOR]

Synaptic devices have gained prominence as viable alternatives to conventional complementary metal‐oxide‐semiconductor‐based (CMOS) electronics in the information processing field owing to their inherent advantages in analog and parallel operations. The potential of synaptic devices has not yet been fully utilized for logic operations because only the conventional binary logic structure has been applied to analog synaptic devices, leading to the loss of advantages unique to analog signals. To resolve this issue, an innovative concept is proposed: an analog logic gate that can perform parallel operations at the device level and is coupled with logic reconfigurations, enabling comprehensive analog computation. This logic gate comprises two synaptic devices with different retention characteristics, adjusted by the side‐chain engineering of an organic polymer. The long‐term and short‐term synaptic devices serve as reconfigurable synapse for logic mode selection and parallel processable logic synapse, respectively. In this study, the reconfigurable and parallel processable synaptic logic circuit is effectively implemented in a personalized disease risk diagnostic system. This innovative approach not only allows for the simultaneous computation of analog‐formed diagnostic data, but also enhances both computing efficiency and system complexity in general synaptic systems. [ABSTRACT FROM AUTHOR]

During the course of disease progression, changes in nucleic acid and non-nucleic acid marker contents can serve as indicators for disease diagnosis. The clustered regularly spaced short palindromic repeat (CRISPR)/Cas12a system, as a natural amplifier, has been widely exploited to construct amplified detection platforms for the detection of various analytes owing to its advantages of simplicity, high activity, and strong specificity. Nowadays, most of the focus is on the use of nucleic acid chains as response elements to activate Cas12a. Consequently, the development of switchable crRNA-based detection methods is urgently needed to expand such a switch's application in the quantification of non-nucleic acid analytes. A powerful and universal fluorescent sensing platform for the detection of non-nucleic acid analytes based on programmable switching of CRISPR/Cas12 activity via modulating crRNA conformation is proposed. In this system, two states, one in which the crRNA sequence is partially caged with a specially designed blocker DNA ("locked state") and the other where native crRNA is regained after the blocker DNA gets lost ("unlocked state"), are modulated through target recognition. When a target is present, the function of the CRISPR/Cas12a system can be rapidly reinstated by switching locking to unlocking to cleave fluorescent reporters for signal output. As a proof-of-concept example, it was demonstrated that this platform could detect three analytes, namely adenosine triphosphate (ATP), glutathione (GSH), and formamidopyrimidine-DNA glycosylase (Fpg), with high specificity and good sensitivity (LODATP = 0.046 μM, LODGSH = 0.1 μM, and LODFpg = 0.2 U mL−1). Moreover, by importing a programmable module, a set of CRISPR/Cas12 system-based logic gates was successfully constructed. Our constructed switchable crRNA-based sensing platform is universal, in which the target binding event is converted into the tunable trans-cleavage of ssDNA reporters via Cas12a, and thus, this platform could be expanded for detecting a wide spectrum of analytes by redesigning the corresponding sequence for target recognition. With its properties of universality, robustness, convenience, and programmability, the present platform indeed provides a useful and practical tool for molecular diagnosis and biomedicine research. [ABSTRACT FROM AUTHOR]

The study presents a novel self‐powered ultraviolet (UV) photodetector harnessing both polarization fields and photovoltaic effects, enabling the realization of ultra‐low power, reconfigurable optoelectronic logic gates. The approach is demonstrated on a CuO/BaTiO3 heterojunction photodetector. The behavior of the photodetector is augmented by the poling effect, aligning the internal electric field of the BaTiO3 through the application of a robust external electric field, thereby facilitating the implementation of optoelectronic logic gates. In the unpoled state, the “XOR” and “OR” logic gates operated at voltages of 750 and −500 µV, respectively. However, upon poling up state, the “XOR” logic gate exhibits reduced operation voltage, operating at 500 µV, while the “OR” logic gate implements clarity at −500 µV. In the unpoled state the “AND” logic gate does not operate; however, upon poling in the downward direction, it operated at −500 µV. The achievement demonstrates successful ultra‐low‐power logic operations, utilizing voltages in the hundreds of micron scale, under a 310 nm wavelength and a light intensity of 0.52 mW·cm−2. Furthermore, controllable polarization electric fields in BaTiO3 enable the operation of “AND” logic gate in the unpoled state, presenting a promising avenue for future research in optoelectronic logic gate design. [ABSTRACT FROM AUTHOR]

A promising alternative for the CMOS technology is the Quantum-dot Cellular Automata (QCA) technology. In this technology, the low-latency, ultra-dense, and low-power consumption digital circuits are designed. Until now, many digital circuits are designed and improved in the QCA technology. The Arithmetic Logic Unit (ALU) is an important digital circuit that designed in this technology. The reversible logic gates such as NOT, Feynman, and Fredkin gates are important elements in the arithmetic circuits and processors design. In addition, considering the cell arrangements has a great influence on the area and speed of execution of computing devices in the QCA technology. This paper's goal is to build a new multilayer QCA Reversible ALU (RALU). In this paper, we used one HN and three Fredkin gates to design and implement a new and efficient RALU circuit in the QCA technology. The proposed QCA RALU circuit is simulated and tested using QCADesigner tool. The simulation results demonstrate that the developed QCA multilayer RALU has 489 cells, 0.36 µm2 area, 3.75 clock cycles delay, 2.02 meV average energy, and 5.41 nW power dissipation. In addition, the comparison indicates that the developed QCA RALU circuit has advantages compared to other QCA RALU circuits with regards to energy, area, latency, and cost. [ABSTRACT FROM AUTHOR]

Implementation of logic gates has been investigated in nonlinear dynamical systems from various perspectives over the years. Specifically, logic gates have been implemented in both single nonlinear systems and coupled nonlinear oscillators. The majority of the works in the literature have been done on the evolution of single oscillators into OR/AND or NOR/NAND logic gates. In the present study, we demonstrate the design of logic gates in bi-directionally coupled double-well Duffing oscillators by applying two logic inputs to the drive system alone along with a fixed bias. The nonlinear system, comprising both bi-directional components, exhibits varied logic behaviors within an optimal range of coupling strength. Both attractive and repulsive couplings yield similar and complementary logic behaviors in the first and second oscillators. These couplings play a major role in exhibiting fundamental and universal logic gates in simple nonlinear systems. Under a positive bias, both the first and second oscillators demonstrate OR logic gate for the attractive coupling, while exhibiting OR and NOR logic gates, respectively, for the repulsive coupling. Conversely, under a negative bias, both the first and second oscillators display AND logic gate for the attractive coupling, and AND and NAND logical outputs for the repulsive coupling. Furthermore, we confirm the robustness of the bi-directional oscillators against moderate noise in maintaining the desired logical outputs. [ABSTRACT FROM AUTHOR]

Optical logic devices are essential functional devices for achieving optical signal processing. In this study, we design an ultra-compact (4.92 × 2.52 μm2) reconfigurable optical logic gate by using inverse design method with DBS algorithm based on Sb2Se3-SOI integrated platform. By selecting different amorphous/crystalline distributions of Sb2Se3 via programmable electrical triggers, the designed structure can switch between OR, XOR, NOT or AND logic gate. This structure works well for all four logic functions in the wavelength range of 1540–1560 nm. Especially at the wavelength of 1550 nm, the Contrast Ratios for XOR, NOT and AND logic gate are 13.77 dB, 11.69 dB and 3.01 dB, respectively, indicating good logical judgment ability of the device. Our design is robust to a certain range of fabrication imperfections. Even if performance weakens due to deviations, improvements can be obtained by rearranging the configurations of Sb2Se3 without reproducing the whole device. [ABSTRACT FROM AUTHOR]

The blockchain-based Electronic Medical Record (EMR) data storage system encounters challenges which are data leakage, insufficient access control, and low retrieval efficiency. In response to these issues, this paper proposes a lightweight searchable encryption and access control system for sharing EMR data securely. The lightweight searchable encryption scheme which is achieved by integrating the trapdoor verification phase with the keyword retrieval phase is constructed using BGG13 + and MP12. User access control is implemented through a Boolean circuit to replace arithmetic operations and thus improve arithmetic efficiency. Since logic operations can reduce the computation time, this paper uses Boolean circuits for user rights verification implementation. In addition, this paper adopts the Bloom filter as the system index to enhance the efficiency of block-chain data retrieval. According to the simulation results, there is a performance advantage of this system over similar systems. [ABSTRACT FROM AUTHOR]

The entanglement of the momentum of light with its spin at interfaces or inside structured media, known as the photonic spin‐Hall effect, holds great promise for various applications, such as beam splitting, focusing, and polarization detection. However, the photonic spin‐Hall effect remains unexplored in the field of logic operation. In this work, the photonic spin‐Hall effect of spoof surface plasmon polaritons (SSPPs) in programmable metamaterial is demonstrated. Moreover, photonic spin‐Hall logic devices based on programmable spoof plasmonic metamaterial are designed, enabling the control of energy flow through the utilization of both spin and digital coding, with examples including SSPPs logic gates such as the "AND" gate, the "NIMPLY" gate (A AND NOT B), the "OR" gate, and the "NOT" gate. The findings introduce the combination of digital coding metamaterial with the photonic spin Hall effect, which offers a powerful and flexible platform for controlling electromagnetic waves in information processing. [ABSTRACT FROM AUTHOR]

All‐optical neural networks have advantages in higher throughput, higher speed as well as lower energy consumption compared to electrical neural networks. Optical neural networks have already shown great potential in various applications; however, the operation speed of the network is limited by the 2D detector as most optical neural networks rely on space to space projection. Here, a space to time projection approach to build diffractive deep neural network (D2NN) is proposed, which can project spatial intensity distribution into time‐domain intensity variation, thus bypassing the detection speed limit of 2D imaging device. Based on this scheme, high‐speed all‐optical logic gates are theoretically analyzed and experimentally realized. In this case, the network's operation speed is only limited by the photodetector (PD), which can reach GHz levels. Moreover, the method will show great advantage when it comes to wavelengths where 2D detectors are not achievable easily such as infrared, terahertz or microwaves. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions, despite being promising ultra‐low energy information carriers with wide bandwidth and nonvolatility, are not used for any universal scalable logic system. Here, a detailed understanding of skyrmion motion in nanowires under different geometries and drive conditions is established. Then, these insights are used to introduce a general Boolean‐universal gate block system with components, emulation, and simulation algorithms. The resulting system can collectively form a scalable, cascadable, and universal skyrmion logic system and produce arbitrary logic designs. The NOR, AND, OR, NAND, XNOR, and FULL ADDER gates are provided here as example demonstrations of the system. The toolkit lays the foundation for bridging the gap between theoretical exploration and practical implementation of skyrmion‐based computing. The skyrmion block components may help reduce energy consumption per logic operation after eliminating Joule heating. The insights and designs may help skyrmions be used in state‐of‐the‐art electronic design automation. [ABSTRACT FROM AUTHOR]

Micromagnetic simulations have been used to create reversible logic gates that utilize magnetic skyrmions as input and output signals. The geometrical design of the logic devices consists of a two-dimensional assembly of ferromagnetic nanotracks, resembling rectangular grooves. Drawing an analogy to the billiard-ball model, this study takes into account elastic collisions between magnetic skyrmions and introduces the concept of control skyrmion. The application of spin-polarized currents to the system induces the motion of magnetic skyrmions along the nanotracks. The synchronized movement of magnetic skyrmions across the operational logic gates, required for their interaction, is achieved by incorporating multiple triangular magnetic notches along the nanotracks. Short polarized current pulses are then applied through the logic gates to facilitate this process. We have successfully implemented the XOR/AND and Full Adder logic gates as well as the reversible Toffoli and Peres logic gates using skyrmion-based architectures for computing. Our results offer valuable guidelines for leveraging magnetic skyrmions as digital signals in skyrmion-based computing systems. [ABSTRACT FROM AUTHOR]

Magnetic skyrmion is a promising information carrier for its low critical driven current density, topological stability, and small size, which has been proposed for various devices such as racetrack memory and logic gates. However, the skyrmion Hall effect originating from Magnus force leads to transverse motion, which hinders the development of skyrmionic device applications. Here, we propose artificial tracks built by standing surface acoustic waves (SSAWs) to suppress the skyrmion Hall effect through micromagnetic simulations. We systematically study the dynamics of an isolated skyrmion under SSAWs and driven currents in a prototype of the ferromagnetic skyrmion system. The skyrmion Hall angle changes from 80° to 0°, where the skyrmion motion is along the driven current. An analytical model considering magnetoelastic energy induced by SSAWs is developed, and a linear relation between the current density and the critical SSAW amplitude to eliminate the skyrmion Hall effect is achieved. Furthermore, a reconfigurable multichannel skyrmion racetrack is constructed through the change of SSAW wavelengths. Our work opens a feasible route for the suppression of skyrmion Hall effect via SSAWs. [ABSTRACT FROM AUTHOR]

Owing to the advanced fabrication technology of silicon, silicon waveguides are particularly attractive for implementing all-optical signal processing devices and switches. Therefore, in this paper, a silicon-on-silica waveguide that consists of four slots arranged in the shape of letter E is proposed to be employed as the building block for simulating fundamental all-optical logic gates (AOLGs), including XOR, AND, OR, NOT, NOR, NAND, and XNOR, at 1.55 μm telecommunications wavelength. The operation concept of these logic gates relies on the constructive and destructive interference that results from the phase difference induced by optical beams that are incident on the E-shaped waveguide. The performance of the target logic gates is assessed against the contrast ratio (CR) metric. Moreover, the dependence of the spectral transmission on the device's key operating parameters is investigated and assessed. Compared to other reported designs, the results obtained by conducting simulations using the finite-difference-time-domain in lumerical commercial software show that the proposed waveguide can operate at a higher speed of 80 Gb/s and attain higher CRs of 36, 39, 35.5, 28.8, 30, 38, and 36.7 dB for logic XOR, AND, OR, NOT, NOR, NAND, and XNOR, respectively. This suggests that by using the proposed scheme, AOLGs could be realized more feasibly with greater performance and faster operation toward satisfying the present and future needs of light wave circuits and systems. [ABSTRACT FROM AUTHOR]

Frequency encoded reconfigurable logic gates OR and AND are designed using interferometric switch based on quantum dot semiconductor optical amplifier (QDSOA) and simulated using MATLAB for the first time as far as our knowledge goes. The amplitude modulation (AM) and quality factor ( Q fe ) are calculated using numerical simulations confirming practical feasibility of the logic gates. This paper also investigates the effect of amplified spontaneous emission (ASE) noise on AM, Q fe and signal-to-noise ratio (SNR) values. AM below 0.005 dB and Q fe more than 30 dB ensure error free operation of the logic gates. [ABSTRACT FROM AUTHOR]

[Display omitted] Due to the complexity of regulatory networks of disease-related biomarkers, developing simple, sensitive, and accurate methods has remained challenging for precise diagnosis. Herein, an "AND" logic gates DNA molecular machine (LGDM) was constructed, which was powered by the catalytic hairpin assembly (CHA). It was coupled with dual-emission CdTe quantum dots (QDs)-based cation exchange reaction (CER) for label-free, sensitive, and ratiometric fluorescence detection of APE1 and miRNA biomarkers. Benefiting from synergistic signal amplification strategies and a ratiometric fluorometric output mode, this LGDM enables accurate logic computing with robust and significant output signals from weak inputs. It offers improved sensitivity and selectivity even in cell extracts. Using dual-emission spectra CdTe QDs, with a ratiometric signal output mode, ensured good stability and effectively prevented false-positive signals from intrinsic biological interferences compared to the approach relying on a single signal output mode, which enabled the LGDM to achieve rapid, efficient, and accurate natural drug screening against APE1 inhibitors in vitro and cells. The developed method provides impetus to streamline research related to miRNA and APE1, offering significant promise for widespread application in drug development and clinical analysis. [ABSTRACT FROM AUTHOR]

We propose a scheme to investigate the spatial modulation of the refractive index in a dense atomic ensemble under the action of the Laguerre–Gaussian (LG) beams. Theoretical derivations based on a density-matrix approach associated with numerical simulations are utilized to study the behaviors of the index of refraction, showing that the azimuthal and radial mode indices (i.e., l 2 and p 2) of the LG beams significantly affect the real and imaginary parts of the refractive index. To be specific, the number of the dispersive peaks is determined by (p 2 + 1) | l 2 | , and there are 2 | l 2 | lossless petals in conjunction with p 2 concentric absorption rings centered on the vortex center. Furthermore, by tuning the phase values of the electric and magnetic components of the electromagnetic field, the index of refraction can be drastically tuned from negative to zero to positive and accompanied by periodic absorption and amplification. This investigation provides a powerful tool for manipulating the index of refraction through a nonlinear interaction between atoms and the vortex beams and suggests potential applications in optical switching, logic gates, and optical storage with spatially varying refractive indices. [ABSTRACT FROM AUTHOR]

Supramolecules are considered a promising approach for molecular logic gates due to their inherent dynamic responsiveness driven by non‐covalent forces. However, the lack of input sequence dependence in these logic gates may lead to misinterpretation of outputs, compromising their reliability. This study proposes an efficient universal supramolecular Förster resonance energy transfer (FRET) platform for logic gates with self‐locking features. Specifically, well‐designed naphthalene‐based monomers serve as energy donors, while dyes such as eosin Y (EY), rhodamine B (RhB), and sulforhodamine 101 (SR101), spanning from yellow to red, are employed as energy acceptors. Leveraging large exciton migration rates (1.21 × 1014 to 1.36 × 1014 L mol−1 s−1) between donor and acceptors, FRET processes are effectively facilitated. Building upon this framework, supramolecular logic gates with self‐locking features are successfully constructed. Notably, in these logic gates, even with the correct truth table, any deviation in the order of inputs can lead to alterations in the original outputs. [ABSTRACT FROM AUTHOR]