Multifunctional Logic Gate Research Articles

Design of Ultra-Compact and Multifunctional Optical Logic Gate Based on Sb2Se3-SOI Hybrid Platform.

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.

All-in-one, all-optical logic gates using liquid metal plasmon nonlinearity

Electronic processors are reaching the physical speed ceiling that heralds the era of optical processors. Multifunctional all-optical logic gates (AOLGs) of massively parallel processing are of great importance for large-scale integrated optical processors with speed far in excess of electronics, while are rather challenging due to limited operation bandwidth and multifunctional integration complexity. Here we for the first time experimentally demonstrate a reconfigurable all-in-one broadband AOLG that achieves nine fundamental Boolean logics in a single configuration, enabled by ultrabroadband (400–4000 nm) plasmon-enhanced thermo-optical nonlinearity (TONL) of liquid-metal Galinstan nanodroplet assemblies (GNAs). Due to the unique heterogeneity (broad-range geometry sizes, morphology, assembly profiles), the prepared GNAs exhibit broadband plasmonic opto-thermal effects (hybridization, local heating, energy transfer, etc.), resulting in a huge nonlinear refractive index under the order of 10−4−10−5 within visual-infrared range. Furthermore, a generalized control-signal light route is proposed for the dynamic TONL modulation of reversible spatial-phase shift, based on which nine logic functions are reconfigurable in one single AOLG configuration. Our work will provide a powerful strategy on large-bandwidth all-optical circuits for high-density data processing in the future.

A multifunctional optical‐thermal logic gate sensor array based on ferroelectric BiFeO3 thin films

AbstractThe growing need to process a diverse range of data has ignited effort in developing new multifunctional logic gate devices. In this article, we report a new form of all‐in‐one logic gate system that exploits the photoresponsivity of a self‐powered multifunctional BiFeO3 (BFO) sensor material. The BFO sensor can not only detect both light intensity and temperature, but it can also execute three common logic gates of “AND”, “OR”, and “NOT” by converting optical and thermal inputs into electrical output. The diverse functionality of the BFO logic gate sensor array utilizes the unique light‐and temperature‐controlled energy band structure and carrier behavior of the BFO material. To demonstrate the potential, a 3 × 3 logic gate sensor matrix is developed, which successfully detected light and temperature distributions, and accurately produced the three basic logic gate operations. This work provides a new route to construct highly integrated multifunctional electronic devices for the advancement of large sensing, communication, and computing operations.image

Realization of optical logic gates using on-chip diffractive optical neural networks

Optical computing is highly desired as a potential strategy for circumventing the performance limitations of semiconductor-based electronic devices and circuits. Optical logic gates are considered as fundamental building blocks for optical computation and they enable logic functions to be performed extremely quickly without the generation of heat and crosstalk. Here, we discuss the design of a multi-functional optical logic gate based on an on-chip diffractive optical neural network that can perform AND, NOT and OR logic operations at the wavelength of 1.55 µm. The wavelength-independent operation of the multi-functional logic gate at seven wavelengths (over a bandwidth of 60 nm) is also studied which paves the way for wavelength division multiplexed parallel computation. This simple, highly-integrable, low-loss, energy-efficient and broadband optical logic gate provides a path for the development of high-speed on-chip nanophotonic processors for future optical computing applications.

Multifunctional acoustic logic gates by valley sonic crystals

The emergence of acoustic logic devices has attracted increasing attention owing to its great potential in logical operations and integrated acoustics. In recent years, various types of acoustic logic gates have successively been demonstrated based on artificial materials. However, simultaneous realization of acoustic logic devices with the characteristics of broad bandwidth and high robustness still poses a great challenge. To overcome this, we numerically design and experimentally demonstrate a multifunctional logic gate based on valley sonic crystals (VSCs). In a designed waveguide composed of two VSCs, a pair of valley edge states can be obtained in the domain wall. Additionally, we experimentally design a multifunctional logic gate composed of four VSCs. The logic functions OR and XOR with the fractional bandwidths of 0.24 and 0.19 can be realized at two output ports, which arises from both valley conservation and linear interference mechanisms. More importantly, we experimentally demonstrate the robustness of the logic gate by introducing a V-shaped defect, and the corresponding logic functions and their bandwidths created by the valley transport of edge states are almost immune to backscattering from the V-shaped defect. Compared with the previous acoustic logic gates, the proposed logic gate has the advantages of multifunctionality, broad bandwidth, and high robustness, which may have practical applications in advanced acoustic devices for computing and information processing.

Versatile Triple-Output Molecular Logic Gate for Cysteine and Silver (I) in Foods and the Environment Based on I-Motif DNA Modulation.

DNA-based molecular logic gates have been developed rapidly but most of them have a single output mode. This study is to develop a triple-output label-free fluorescent DNA-based multifunctional molecular logic gate with berberine as a fluorescent signal and a Ag+-aptamer as a recognition matrix. The Ag+-aptamer has been identified to switch from a random coil to an i-motif structure of C-Ag+-C from a Ag+-induced responsive conformational change. As a fluorescent probe, berberine is ultrasensitive to the changes of microenvironments, and the binding to i-motif DNA's more rigid structure causes a significant increase in fluorescence, anisotropy, and lifetime. The addition of cysteine to the berberine/C-Ag+-C system disintegrates the i-motif DNA structure because of the strong coordination between Ag+ and cysteine, and then the triple-output signals are almost retrieved. Given this, a highly sensitive triple-output molecular logic gate for the analyses of Ag+ and cysteine is constructed with high specificity. Moreover, this simple and cost-effective molecular logic gate has been applied for the detection of cysteine and Ag+ in various real environmental samples including river water, PM2.5, soil, and food samples with satisfactory recoveries from 89.83 to 106.04%.

Multi-functional all-optical photonic crystal logic gate using nonlinear directional coupler

Multi-functional all-optical photonic crystal logic gate using nonlinear directional coupler

Linear multi-functional logic gate in a three-core photonic crystal fiber

The growth of transmission rates in optical fibers can increase the demand for devices that perform network node processing. Usually, such devices achieve complex optical signal processing through high non-linearity effects and optoelectronic devices. In this work, we present the numerical acquisition of a configurable multi-function logic gate in which the OR and AND gates can be enabled based on the logic values entered in a selector. Our device consists of a single piece of three-core PCF, with linear pulse propagation, and without the need for any other mechanisms. This result presents evidence that information processing within functional fibers is possible and might be achieved using only fiber design.

Design, simulation and optimization of all-optical NOT/XOR logic gates for use in the new photonic crystal 4×2 encoder

In this paper, in a unique work, the structure of NOT / XOR multifunctional all-optical logic gates is provided using interference effects in 2D photonic crystal structures for use in photonic integrated circuits of next generation. The applicability of the structure has been analyzed by modifying the output waveguide to optimize it and finally examining its performance by placing several structures together for using in optical integrated circuits. In both basic and optimized structures, the contrast ratio, response time, and data transfer rate were measured 36 dB, 0.176 ps and 5.68 Tbit/s, respectively. Appropriate output results along the very small size of about 75.78 µm2, these circuits make the logic very proper for use in optical integrated circuits. For this purpose, in a more complete work, an all-optimal 4×2 Encoder has been designed using optimized structure. In this structure, the contrast ratio is about 13.2 dB, the response time is 0.168 ps and the data transfer rate is 6 Tbit/s. The results of this NOT/XOR basic and optimized all-optical logic gate structure as well as 4×2 Encoder indicate the high flexibility and applicability of these designs for use in structures in this field for use in optical integrated circuits. In this paper, the Plane Wave Expansion method is used to obtain and analyze the photonic band gap range and the Finite-difference time-domain is used to analyze and simulate the designed structures.

Conceptual design of magnonic majority-logic gate based on channeling of spin waves in domain walls

A three-input majority gate, which operates on the basis of majority decisions, can function as multifunctional Boolean logic gates. Here, we report a micromagnetic simulation study of a specially devised magnonic majority-logic gate that utilizes channeling of spin waves into narrow domain walls. Our model system is a four-armed cross structure where low-energy spin waves are guided and channeled along Néel-type domain walls and then interact with a single magnetic vortex positioned at the cross-point. After exciting spin waves simultaneously from the ends of three individual arms where input binary digits are encoded using spin-wave phase information, the phases of spin waves passing through the cross-point (after being scattered from the vortex) are measured as output binary digits at the end of the remaining single output arm. Consequently, the majority of the input variables determines the output signal, which is a clear sign of a majority gate. Furthermore, by setting a control input, our proposed single structure can perform multiple operations of AND-, OR-, NAND-, and NOR-gates. Finally, the gate structure and channeling spin waves into domain walls/their interaction with a vortex core have the additional merits of being free of the Joule heating typically encountered in conventional electronic devices and of having long coherence lengths.

Acoustic Multifunctional Logic Gates and Amplifier Based on Passive Parity-Time Symmetry

Acoustic analogue computation and signal processing are of great significance; however, it is challenging to realize acoustic computing devices because of their limitations of single function and complex structure. Here, an acoustic multifunctional device, which can gate or amplify acoustic waves without resorting to altering the frequency and structure using a passive acoustic parity-time (PT)-symmetric metamaterial, is realized theoretically and experimentally. The metamaterial is constructed by five lossless-loss periodically distributed media, which are modulated to achieve passive PT symmetry. At the coherent perfect absorber emitter point in the broken PT-symmetric phase, the logic gates (and, or, xor, and not) and small signal amplifier are realized in a single system by adjusting the phase and amplitude differences between two incoming beams, respectively. This work provides a route for the connection between PT symmetry and the acoustic metamaterial, which has potential applications in acoustic modulation and acoustic multifunctional devices.

Nano‐scale multifunctional logic gate based on graphene/hexagonal boron nitride plasmonic waveguides

The concept and analysis of a nano-scale multifunctional logic gate based on graphene/hexagonal boron nitride (h-BN) plasmonic waveguides at a wavelength of 7.5 µm are presented. By using graphene as a metamaterial with outstanding electro-optical properties, various logical operations including AND, OR, and XOR are implemented. The proposed multifunctional structure supports surface plasmons (SPs) whose dispersion properties can be controlled by applying an electrical field to graphene. The effects of the incident polarisation and the substrate of graphene on the transmission of SPs are investigated. Simulations by finite difference time domain method show that the extinction ratios for the presented logical operations are higher than 15 dB. Also, the structure has a compact footprint of 1.12 µm2 which is suitable for using in integrated photonic circuits. This provides a path for the development of novel nano-scale practical on-chip applications such as plasmonic memory devices.

Nanowire network–based multifunctional all-optical logic gates

All-optical nanoscale logic components are highly desired for various applications because light may enable logic functions to be performed extremely quickly without the generation of heat and cross-talk. All-optical computing at nanoscale is therefore a promising alternative but requires the development of a complete toolbox capable of various logic functionalities. We demonstrate nanoscale all-optical switches by exploiting the polarization-dependent light emission property of crossbar InP and AlGaAs nanowire networks. These networks can perform various logic operations, such as AND, OR, NAND, and NOR binary logic functions. Furthermore, on the basis of these logic operations, our networks successfully enable all-optical arithmetic binary calculations, such as n-bit addition, to be conducted. Our results underscore the promise of assembled semiconductor nanowire networks as a building block of on-chip all-optical logic components for future nanophotonics.

Ultra-compact all-optical phase-controlled NAND, OR, XOR, XNOR, and NOT multi-function logic gate

We propose a novel multi-function logic gate in order to attain all NAND, OR, XOR, XNOR, and NOT logic functions in a single structure with controlling the phase of input lights. Beam propagation analysis illustrates that the highest insertion loss of structure is − 0.05 dB in whole C-band. The output on–off logic level contrast ratio for NAND, OR, XOR, XNOR, and NOT logic functions are 28.2, 28.2, 30.2, 30.2, and 30.2 dB, respectively. The structure which is composed of one multimode interference region with ultra-small size of 1.5 µm × 12.2 µm is a promising candidate for ultra-compact systems.

A single MEMS resonator for reconfigurable multifunctional logic gates

Despite recent efforts toward true electromechanical resonator-based computing, achieving complex logic functions through cascading micro resonators has been deterred by challenges involved in their interconnections and the large required array of resonators. In this work we present a single micro electromechanical resonator with two outputs that enables the realization of multifunctional logic gates as well as other complex logic operations. As examples, we demonstrate the realization of the fundamental 2-bit logic gates of OR, XOR, AND, NOR, and a half adder. The device is based on a compound resonator consisting of a clamped-guided electrostatically actuated arch beam that is attached to another resonant beam from the side, which serves as an additional actuation electrode for the arch. The structure is also provided with an additional electrothermal tuning capability. The logic operations are based on the linear frequency modulations of the arch resonator and side microbeam. The device is compatible with CMOS fabrication process and works at room temperature.

Multifunctional logic gates based on silicon hybrid plasmonic waveguides

Nano-scale Multifunctional Logic Gates based on Si hybrid plasmonic waveguides (HPWGs) are designed by utilizing the multimode interference (MMI) effect. The proposed device is composed of three input waveguides, three output waveguides and an MMI waveguide. The functional size of the device is only 1000 nm × 3200 nm, which is much smaller than traditional Si-based all-optical logic gates. By setting different input signals and selecting suitable threshold value, OR, AND, XOR and NOT gates are achieved simultaneously or individually in a single device. This may provide a way for ultrahigh speed signal processing and future nanophotonic integrated circuits.

A multifunctional logic gate by means of a triple-chromophore fluorescent biothiol probe with diverse fluorescence signal patterns.

A novel multifunctional logic gate based on a triple-chromophore (coumarin-NBD-flavylium, CNF) fluorescent biothiol probe with diverse fluorescence signal patterns was rationally designed and synthetized. On the new triad CNF, diverse logic operations such as OR, TRANSFER, INH, NOT, and YES logic gates were achieved by using biothiols and fluorescence signal patterns as the multiple inputs and outputs, respectively.

A photoswitchable diarylethene heterodimer for use as a multifunctional logic gate

A photoswitchable diarylethene heterodimer was prepared and its applications to logic gates were successfully demonstrated.

Multiple logic functions from extended blockade region in a silicon quantum-dot transistor

We demonstrate multiple logic-functions at room temperature on a unit device of the Si single electron transistor (SET). Owing to the formation of the multi-dot system, the device exhibits the enhanced Coulomb blockade characteristics (e.g., large peak-to-valley current ratio ∼200) that can improve the reliability of the SET-based logic circuits. The SET displays a unique feature useful for the logic applications; namely, the Coulomb oscillation peaks are systematically shifted by changing either of only the gate or the drain voltage. This enables the SET to act as a multi-functional one-transistor logic gate with AND, OR, NAND, and XOR functions.

Investigation of a simultaneous multifunctional photonic logic gate based on bidirectional FWM

We demonstrate a multi-functional photonic logic gate for RZ-PolSK signals based on four wave mixing (FWM) in highly nonlinear fiber (HNLF). Bidirectional operation with one spool of HNLF is implemented numerically at 40Gb/s. The basic logic arithmetics, such as XOR, AB¯,A¯B, XNOR, AND, NOR, and complex logic functions such as half-subtracter, half-adder, comparator and decoder are simultaneously realized by adjusting the polarization controllers. This novel structure is low-cost and rather flexible. Proper logic results, clear waveforms and high Q factors of eye diagrams are presented. Simulation analysis shows that bit error-free operation for the logic gate can be obtained when the wavelength separation is from −7 to 6nm for two input signals. The impact of the input power on the Q factor is also investigated. Due to the femoto-second response time of Kerr-effect in HNLF we used in the scheme, the logic gate has great potential in future ultra-high speed optical transmission systems.