XNOR Logic Gates Research Articles

Primordial Molecular 1-Bit Magnitude Comparator in consort with Excitation-Guided mouldable Logic Systems: A guided design of Regular Interactions between Molecules.

In addition to designing certain excitation modulated logic systems, we have created the first-ever genuine molecular 1-bit magnitude comparator, using acid and base guided varied absorption responses at separate channels. Designed and manufactured Bifunctional Bis(indolyl)methane Derivative (1) demonstrates distinct optical responses (in UV-visible and fluorescence mode) to a range of chemical stimuli (acid, base, Hg2+, Cu2+, EDTA, GSH, etc.) in aqueous medium. Intriguingly, the compound's excitation-modulated fluorescence responses appeared to change at different detection channels depending on whether the aforementioned analytes were present or not. We have proposed not only an excitation driven logic system with switchable molecular IMPLICATION and XNOR logic gates, but also a molecular 1-bit magnitude comparator in our proposal. A second excitation driven logic system with switchable molecular COMPLEMENT and NOR logic gates was also designed with two different optical channels and used Hg(II) & Cu(II) as chemical inputs.

Investigation of a Nonlinear XNOR Logic Gate Based on an Induced Nonlinear Phase Shift of Spin Waves

Introduction. Recent years have seen a growing interest in studying the nonlinear properties of spin waves. Nonlinear phenomena, such as envelope solitons, nonlinear frequency shifts of intense spin waves, and etc., have attracted particular attention. However, a number of important issues remain to be underexplored, including the problem of induced nonlinear phase shift of spin waves. The relevance of this problem is related to the need to develop spin-wave logic gates that could be controlled by changing the spin wave phase.Aim. To study a nonlinear XNOR logic gate whose operation is based on the induced nonlinear phase shift of a spin wave.Materials and methods. An original theory is used to simulate the frequency response of a nonlinear XNOR logic gate. The operating principle of the nonlinear XNOR logic gate is substantiated. The possibility of implementing the nonlinear XNOR logic gate in a circuit similar to a spin-wave Mach-Zehnder interferometer is experimentally demonstrated.Results. An experimental study of the induced nonlinear phase shift of operating signals incident on identical nonlinear spin-wave phase shifters located in the arms of the logic gate was carried out. It is shown that an increase in the pump signal power up to 60 mW, supplied to nonlinear phase shifters, changes the induced nonlinear phase shift of the operating signal by more than 180°. Hence, nonlinear phase shifters can be used for constructing spin-wave logic gates. In addition, the operating principle of a spin-wave logic gate was experimentally studied. It is shown that the XNOR logical function is implemented in the low-frequency part of the device’s frequency response characteristic.Conclusion. Numerical simulation of the characteristics of a nonlinear XNOR logic gate based on the Mach-Zehnder interferometer circuit was carried out. It is shown that its logical functions are implemented due to the effect of an induced nonlinear phase shift of spin waves in nonlinear phase shifters located in different arms of the logic gate.

Design of Ultrasmall Plasmonic Logic Gates Based on Single Nanoring Dielectric-Metal-Dielectric Waveguide

This paper proposes a new configuration of dielectric-metal-dielectric (DMD) waveguides to design optical logic gates. Seven plasmonic logic gates, including NOT, OR, AND, NAND, NOR, XOR, and XNOR, are realized by one nanoring and four DMD plasmonic waveguides. To realize the logic gates, an ultrasmall size of 300 nm × 300 nm device is designed. The performance of the plasmonic logic gates is based on constructive and deconstructive interference between input and control ports. To evaluate the logic state of the output port, the threshold transmission limit is assumed to be 0.35. The transmission ratio, T, contrast ratio, CR, modulation depth, MD, insertion loss, IL, and contrast loss, CL, parameters measure the seven logic gates’ performance. A maximum T of 232% is obtained for AND, OR, and XNOR logic gates. Simulation results show that the dimensional parameters are optimized because of very high MD for all seven logic gates. Maximum values of CR and CL are obtained for the NOT gate. For the AND gate, a minimum IL value is achieved. The studied plasmonic logic gates can be employed in building blocks of all-optical signal-processing nanocircuits and nanophotonics devices. The finite element method (FEM) simulates the structure with COMSOL Multiphysics 5.4 software.

Nanoscale plasmonic logic gates design by using an elliptical resonator.

This study implemented AND, NAND, OR, XOR, NOR, XNOR, and NOT plasmonic logic gates using the finite element method. The all-optical nanoscale logic gates were designed using a single structure based on the technology of insulator-metal-insulator nanoscale plasmonic waveguides. The phase of optical waves and the position of the control and input ports are the most important factors for attaining the optimal transmission value based on interference between the input and control ports. The transmission threshold is 35%, and 850 nm is the operating wavelength. This design creates nanoscale logic gates with a structure dimension of 250nm×250nm. The transmission threshold, modulation depth, contrast ratio, and insertion loss criteria were proposed to evaluate the efficacy of the all-optical gates.

Field-free spin–orbit devices via heavy-metal alloy with opposite spin Hall angles for in-memory computing

With the advantages of high speed, low energy consumption, and non-volatility, spin–orbit devices are promising to be used in the field of in-memory computing. However, for large-scale integration, a simpler field-free switching scheme needs to be further explored. Here, we prepared field-free spin–orbit devices based on the PtW alloy layer with competing spin currents. The preparation of such devices is friendly to integration, because there is no requirement of introducing additional processing technology. Only the traditional heavy-metal layer is needed to be replaced by an alloy layer with opposite spin Hall angles. A series of positive and negative pulsed current tests have shown a stable field-free magnetization switching in the Ta/PtW/Co/AlOx/Pt device. The programmable Boolean logic of NAND and NOR were performed in a single device by changing the initial magnetization state. In addition, a pair of devices were connected with always opposite magnetizations to implement the XNOR logic gate, which can be applied to perform the dot product operation in the binary neural network. Based on the spin XNOR gates, a three-layer binary neural network achieves 89% recognition accuracy of handwritten digits. Our findings pave the way to efficient in-memory computing applications.

Design and application of memristor hybrid logic circuit

To address the large area and high power consumption issues in traditional integrated circuits, an improved design of nanoscale memristor is used to realize the adder and multiplier in digital logic circuits. The OR and AND gates of the memristor's MRL structure are used to design the XOR and XNOR logic gates of the 2T-4M structure. A full adder is created by combining these logic gates with CMOS, where the CMOS inverter improves signal drive. By improving the 2T-4M structure, a new 2T-4M logic module is implemented, and a 2-bit binary multiplier is designed based on this module. LTspice simulation ensures that the circuit design is correct. When compared to the previously reported MRL full adder and 2-bit binary multiplier, the full adder significantly reduced the number of components, improved the delay time by 53.3$%$, and reduced power consumption by 1.93 mW. The 2-bit binary multiplier design also has some advantages in terms of total component count, requiring only 18 in total. Finally, a full adder is used to create an encrypted array circuit to encrypt and decrypt the image, proving the circuit's feasibility in practical application.

Design, Photochemistry, Logic Gates Behavior and Antibacterial Evaluation of ICT Systems based on 1,8-naphthalimides.

Ace naphthene as a primary material was nitrated and further reacted by various processes such as oxidation, imidation and amination in order to obtain dyad 5. The dyad 5 fluoresces in solvents of different polarity and the emission is shifted bathochromically with increasing the solvent polarity due to ICT enhancement, The fluorescent enhancement is greatest in case of chloroform (ФF = 0.48) on excitation at 420nm,The influences of the pH on dyad 5 were also investigated, The results can be considered as representing off-on-off states. Dyad 5 executes two input XNOR logic gates, towards H+ and HO- ions, "off-on-off" switching behavior between H+ and HO- ions was observed, The synthesized compounds were tested for antimicrobial activity of Gram-positive and Gram-negative bacteria, The compounds tested have a good antibacterial activity as compared with standard compound (Gentamycin).

320 Gb/s all-optical logic operations based on two-photon absorption in carrier reservoir semiconductor optical amplifiers

When a train of optical pulses is injected, two-photon absorption (TPA)-induced pumping results in significant and fast gain and phase shifts in the carrier reservoir semiconductor optical amplifier (CR-SOA). Therefore, in this work, the effect of TPA on all-optical (AO) exclusive-OR (XOR), AND, NOT-OR (NOR), OR, NOT-AND (NAND), and exclusive-NOR (XNOR) logic operations using CR-SOAs is theoretically implemented for the first time at 320 Gb/s. The XOR, AND, NOR, NAND, and XNOR logic gates are implemented using the Mach-Zehnder interferometer, which has two symmetrical CR-SOAs in each of its two arms, whereas the OR logic gate is produced by combining a CR-SOA with a delayed interferometer. The quality factor (QF) and the associated bit error rate (BER) metrics are employed to evaluate the operations’ performance. The obtained simulation results indicate that when exploiting TPA in CR-SOAs the target Boolean functions can be executed with QF and BER that are more than acceptable than without TPA at a high speed up to 320 Gb/s. Various circuits of enhanced logic functionality, such as AO half-adder, latches, comparator, half-subtractor, and encoder can be implemented by combing the presented AO gates and hence exploiting the ultrafast TPA-induced gain and phase changes in CR-SOAs. Furthermore, the potential of CR-SOAs as nonlinear elements is systematically and thoroughly established for a wide suite of AO logic operations.

Multifunctional logic gates based on resonant transmission at atomic-plasmonic structure

Regarding the confinement of light at nanoscale dimensions in plasmonic structures, we try to show the impact of hot atomic vapor spectroscopy on a miniaturized scale. In such a combined structure, resonant coupling of the atom to plasmonic mode provides diverse ways to control the optical response of the system. We fabricate an atomic plasmonic cell based on Rubidium atomic vapor and gold plasmonic thin film onto the Kretschmann setup to introduce resonant coupling (EIT-like) of atom-plasmons as a tunable all-optical bandpass filter, switch, or logic gates. These all-optical devices such as NOR and XNOR logic gates are well done based on the filter by incidence angle of light, temperature as well as the external magnetic field. We believe the possibility of easy modulation of atomic susceptibility, not only through direct alteration on atoms but also through common methods available for modulation of plasmonic mode, has the potential to design and fabricate modern all-optical devices.

A Polarization-Switching, Charge-Trapping, Modulated Arithmetic Logic Unit for In-Memory Computing Based on Ferroelectric Fin Field-Effect Transistors.

Nonvolatile logic devices are crucial for the development of logic-in-memory (LiM) technology to build the next-generation non-von Neumann computing architecture. Ferroelectric field-effect transistors (Fe FET) are one of the most promising candidates for LiMs because of high compatibility with mainstream silicon-based complementary metal-oxide semiconductor processes, nonvolatile memory, and low power consumption. However, because of the unipolar characteristics of a Fe FET, a nonlinear XOR or XNOR logic gate function is difficult to realize with a single device. In addition, because single Fe polarization switch modulation is available in the devices, a reconfigurable logic gate usually needs multiple devices to construct and realize fewer logic functions. Here, we introduced polarization-switching (PS) and charge-trapping (CT) effects in a single Fe FET and fabricated a multi-field-effect transistor with bipolar-like characteristics based on advanced 10 nm node fin field-effect transistors (PS-CT FinFET) with 9 nm thick Hf0.5Zr0.5O2 films. The special hybrid effects of charge-trapping and polarization-switching enabled eight Boolean logic functions with a single PS-CT FinFET and 16 Boolean logic functions with two complementary PS-CT FinFETs were obtained with three operations. Furthermore, reconfigurable full 1 bit adder and subtractor functions were demonstrated by connecting only two n-type and two p-type PS-CT FinFET devices, indicating that the technology was promising for LiM applications.

Proposal of a Cascade Photonic Crystal XOR Logic Gate for Optical Integrated Circuits with Investigation of Fabrication Error and Optical Power Changes

A compact and simple structure is designed to create an all-optical XOR logic gate using a two-dimensional, photonic crystal lattice. The structure was implemented using three waveguides connected by two nano-resonators. The plane wave expansion method was used to obtain the photonic band gap and the finite-difference time-domain method was used to investigate the behavior of the electromagnetic field in the photonic crystal structure. Examining the high contrast ratio and high-speed cascade, all-optical XOR on a chip, the effects of fabrication error and the changes in the input optical power showed that the structure could be used in optical integrated circuits. The contrast ratio and data transfer rate of the cascade XOR logic gate were respectively obtained as 44.29 dB and 1.5 Tb/s. In addition, the designed structure had very small dimensions at 158.65 μm2 and required very low power to operate, which made it suitable for low-power circuits. This structure could also be used as a NOT logic gate. Therefore, an XNOR logic gate can be designed using XOR and NOT logic gates.

FPGA Realization of Logic Gates using Neural Networks

The real time systems are designed by using analog and digital sub systems with control logic. In the design of digital sub systems the logic gates are the major building blocks. The Neural Networks found many applications in the areas of pattern recognition, prediction, artificial intelligence and other applications. Most of the Neural Network designs are realized by using software domain and hardware domains. This paper presents the hardware realization of logic gates using Neural Network. The logic gates like NAND, AND, NOR, OR, NOT, BUFFER are realized by using single layer neural network. The XNOR and XOR logic gates are realized by using structural representation of neural network based universal NAND gates. All the logic gates are realized by using Verilog HDL with Xilinx Vivado Design suite targeting for Xilinx Zynq-7000 SoC Evaluation Board. The Neural Network based logic gates are simulated for different test cases. Index Terms: Neural Network, Logic Gate, Zynq-7000 SoC, Verilog HDL, Xilinx Vivado EDA tool.

Cascade Strand Displacement and Bipedal Walking Based DNA Logic System for miRNA Diagnostics.

DNA logic gated operations empower the highly efficient analysis of multiplex nucleic acid inputs, which have attracted extensive attention. However, the integration of DNA logic gates with abundant computational functions and signal amplification for biomedical diagnosis is far from being fully achieved. Herein, we develop a bipedal DNA walker based amplified electrochemical method for miRNA detection, which is then used as the basic unit for the construction of various logic circuits, enabling the analysis of multiplex miRNAs. In the bipedal walking process, target triggered strand displacement polymerization is able to produce a large number of strands for the fabrication of three-way junction-structured bipedal walkers. The following catalytic hairpin assembly ensures the walking event and the immobilization of signal probes for output. Ultrahigh sensitivity is realized due to the integration of dual signal amplification. In addition, under logic function controls by input triggered cascade strand displacement reactions, NOT, AND, OR, NAND, NOR, XOR, and XNOR logic gates are successfully established. The as-developed DNA logic system can also be extended to multi-input modes, which holds great promise in the fields of DNA computing, multiplex analysis, and clinical diagnosis.

Ultrafast and Energy-Efficient Ferrimagnetic XNOR Logic Gates for Binary Neural Networks

Ultrafast current-driven domain wall (DW) motions have been realized in ferrimagnetic (FiM) nanowires. However, the FiM dynamics can be significantly affected by the Joule-heating. In this work, we propose a highly efficient XNOR logic gate by properly leveraging the thermal effect on the FiM DW motions. Its functionality and advantageous performance have been confirmed by the micromagnetic simulations. Moreover, majority logic and full adder functions can also be reconfigured based on the proposed scheme. Lastly, a fully FiM DW based binary neural network (BNN) is built, which provides low energy consumption, short delay and excellent accuracy.

A novel proposal based on 2D linear resonant cavity photonic crystals for all-optical NOT, XOR and XNOR logic gates

Abstract In this paper, we are going to propose a novel structure of all-optical NOT, XOR and XNOR logic gates are presented using a two-dimensional photonic crystal (2D-PhC). This structure is optimized by varying the radius of the cavity, to obtain a quality factor Q = 1192, and also has several ports of entry and one port of output. The size of each structure is equal to 85.8 μm2. The contrast ratios for the structures proposed all-optical NOT, XOR and XNOR logic gates between levels “0” and “1” are, respectively, 25.08, 25.03, and 14.47 dB. The response time for the three logical gates is 8.33 ps, and the bit rate is calculated at about 0.12 Tbit/s, all simulations are based on both numerical methods such as finite difference time domain (FDTD) and plane wave expansion (PWE). Designed logic gates are characterized by low power consumption, compactness and easy integration.

Design analysis and applications of all-optical multifunctional logic using a semiconductor optical amplifier-based polarization rotation switch

In this communication, a new semiconductor optical amplifier (SOA)-based module for multi-valued logic units using the cross-polarization modulation effect is proposed and analyzed. The design is simple and compact, consisting of only three SOAs and a few passive optical elements. SOAs have very low switching power (< 1mW), and are very small (< 1 mm) and integrable into modern optical integrated circuits. Being multifunctional, the design is versatile; it can function as a demultiplexer, comparator, half adder, half subtractor, and as basic (OR, AND), universal (NOR, NAND), XOR, and XNOR logic gates. This design follows a tree architecture, operates at very high speed (~ 100Gbit/s), and provides a good Q factor (30 dB or more). The corresponding bit error rate (BER) is very low (~ 10–24). In this work, a relative eye opening as large as 90.4% is calculated. The variations in Q and BER with noise and control power are also investigated.

All-optical logic gates using dielectric-loaded waveguides with quasi-rhombus metasurfaces

Nanostructure and nanoantenna-based all-optical (AO) devices have attracted significant research interests in recent years due to their small size, high information capacity, ultrafast processing, low power consumption, and overall practicality. Here, in this Letter, we propose a novel metasurface having quasi-rhombus-shaped antennas to modulate optical modes in a dielectric-loaded waveguide for the realization of a complete family of logic gates including NOT, AND, OR, XOR, NAND, NOR, and XNOR. These logic operations are realized using destructive and constructive interferences between the input optical signals. The high contrast ratios of about 33.39, 27.69, and 33.11 dB are achieved for the NAND, NOR, and XNOR logic gates, respectively, with the speed as high as 108 Gb/s.

Performance analysis of all-optical NAND, NOR, and XNOR logic gates using photonic crystal waveguide for optical computing applications

All-optical photonic integrated devices have gained great attention in the field of optical computing and large-scale integration. All-optical logic gates are useful for optical signal processing and optical communication network. The flexible devices presented here satisfy the functionality of NAND (NOT-AND), NOR (NOT-OR), and XNOR (exclusive NOR) logic gates using only one structure with proper changes in the phase of an applied light signal. The design of all-optical logic gates is implemented with photonic crystal waveguides using square lattice silicon rods. The performance of the structure is simulated, verified, and analyzed by the finite-difference time-domain method, with the principle of interference effect at a wavelength of 1550 nm. The contrast ratio (CR) of NAND, NOR, and XNOR logic gates is 17.59, 14.3, and 10.52 dB, respectively, with an optimized size of 7.2 μm × 5.4 μm.

Chiral Magnonics: Reprogrammable Nanoscale Spin Wave Networks Based on Chiral Domain Walls.

SummarySpin waves offer promising perspectives as information carriers for future computational architectures beyond conventional complementary metal-oxide-semiconductor (CMOS) technology, owing to their benefits for device minimizations and low-ohmic losses. Although plenty of magnonic devices have been proposed previously, scalable nanoscale networks based on spin waves are still missing. Here, we demonstrate a reprogrammable two-dimensional spin wave network by combining the chiral exchange spin waves and chiral domain walls. The spin-wave network can be extended to two dimensions and offers unprecedented control of exchange spin waves. Each cell in the network can excite, transmit, and detect spin waves independently in the chiral domain wall, and spin-wave logics are also demonstrated. Our results open up perspectives for integrating spin waves into future logic and computing circuits and networks.

Ultracompact tunable bifunctional XOR and XNOR photonic crystal logic gates

Ultracompact simultaneous XOR and XNOR logic gates are proposed and analyzed. The suggested design is based on two-dimensional Si photonic crystal (PhC) with a central hole infiltrated by nematic liquid crystal (NLC) of type E7. The plane wave expansion method is used to obtain the photonic bandgap for both transverse electric mode and transverse magnetic mode. Further, the transmission through the proposed logic gates is calculated by the full vectorial finite element method. The numerical results show that the reported XOR and XNOR logic gates can be operated around wavelength of 1500 nm. In addition, the operation of the designed logic gates can be switched on/off by controlling the NLC biasing state. Such PhC logic gates have a compact size of 47 μm2 and can achieve a large contrast ratio of 26 dB. Therefore, the suggested design has advantages in terms of tunability, low power consumption, compact size, simplicity, and compatibility with nowadays fabrication technology, which will be suitable for photonic integrated circuits.