OR Logic Gates Research Articles

Thermal calculator

Thermal computing is a promising alternative to electronics, which typically fail in harsh environments such as high temperatures and ionizing radiation. In this work, we built and simulated a thermal calculator based on thermal logic gates that can perform similar operations as their electronic counterparts. We present the design and modeling of thermal AND, OR and NOT logic gates, achieved through the coupling between near-field thermal radiation and MEMS thermal actuation. In the process, we also developed two novel non-linear thermal expansion designs of microstructured chevron beams. These results are significant breakthroughs in the field of thermal computation science and technology as they demonstrate thermal computing at high temperatures based on demonstrated and easy to manufacture NanoThermoMechanical diodes and transistors.

Experimental AND and OR Logic Gates With MZI and SOA Using PAM Modulation

One of the main limitations of optical communication systems is the current need for optoelectronic conversions in intermediate devices, which do not reach the transmission rates of optical fibers of terabits per second. In this work, we investigated the obtaining of logic gates through a configuration of a Mach–Zehnder interferometer with a semiconductor optical amplifier (SOA) as the unbalancing element of the interferometer. We experimentally studied three different scenarios of input power for a continuous wave regime and one scenario for the PAM regime, both with varying levels of gain of the SOA. As a result, we obtained the AND and OR logic gates in all scenarios in a wide range of gain of the SOA, besides the logic functions 0 and 1 in some of the cases. We confirm the quality of these logic gates by the precision rate regarding the threshold of 0.4 dB above and below the central limit, according to recommendations from the literature. We highlight that the technique used in this experiment is much less complex than most of those described in the literature. The use of pulse amplitude modulation (PAM) suggests a simpler way for controlling logic gates, once we can obtain those by simply changing the injection current applied by the SOA. The experimental obtaining of such logic gates is relevant for all-optical logic circuits that are proposed to optimize the current optical communication systems.

Threshold-Type Binary Memristor Emulator Circuit

A floating memristor emulator composed of off-the-shelf devices is presented to mimic the dynamics of threshold-type binary memristor. The diodes combined with proportional amplifier circuits are used to model the threshold sensitive behavior. By utilizing a bistable circuit, non-volatility and binary characteristic of the memristor emulator are implemented. The impacts of circuit parameters including resistance and capacitance on the memristor properties are explicated. For instance, the ratio of high memristance to low memristance can be changed by altering the specified resistances. Simulation results validate the feasibility of the proposed memristor emulator circuit. Tunable thresholds, a great memductance ratio, binary characteristic, and non-volatility of the memristor emulator are demonstrated experimentally under the inputs of sinusoidal signal and a series of pulses. In addition, state switching rule of the memristor are tested experimentally through applying pulse signals with different frequency or amplitude. Finally, memristor ratioed logic (MRL) circuits containing OR, AND, and XOR logic gates are used to verify the application of the proposed emulator. The emulator can be operated with floating connection and applied in various memristive circuits. Hence, it can offer a platform for the research of the memristor-based applications.

Simultaneous Detection of Different Zika Virus Lineages via Molecular Computation in a Point-of-Care Assay.

We have developed a generalizable “smart molecular diagnostic” capable of accurate point-of-care (POC) detection of variable nucleic acid targets. Our isothermal assay relies on multiplex execution of four loop-mediated isothermal amplification reactions, with primers that are degenerate and redundant, thereby increasing the breadth of targets while reducing the probability of amplification failure. An easy-to-read visual answer is computed directly by a multi-input Boolean OR logic gate (gate output is true if either one or more gate inputs is true) signal transducer that uses degenerate strand exchange probes to assess any combination of amplicons. We demonstrate our methodology by using the same assay to detect divergent Asian and African lineages of the evolving Zika virus (ZIKV), while maintaining selectivity against non-target viruses. Direct analysis of biological specimens proved possible, with crudely macerated ZIKV-infected Aedes aegypti mosquitoes being identified with 100% specificity and sensitivity. The ease-of-use with minimal instrumentation, broad programmability, and built-in fail-safe reliability make our smart molecular diagnostic attractive for POC use.

Cascadable microelectromechanical resonator logic gate

Micro/nano-electromechanical resonator-based logic elements have emerged recently as an attractive potential alternative to semiconductor electronics. The next step for this technology platform to make it into practical applications and to build complex computing operations beyond the fundamental logic gates is to develop cascadable logic units. Such units should produce outputs that can be used as inputs for the next logic units. Despite the recent developments in electromechanical computing, this requirement has remained elusive. Here, we demonstrate for the first time a conceptual framework for cascadable logic units. Cascadability is experimentally demonstrated through two case studies; one by cascading two OR logic gates. The other case is the universal NOR logic gate realized by cascading an OR and a NOT gate. The logic operations are performed by on-demand activation and deactivation of the second mode of vibration of a clamped-clamped microbeam resonator. We show that the demonstrated approach significantly lowers the complexity and number of microresonator-based logic functions compared to the CMOS-based counterparts, which improves energy efficiency. This can potentially lead toward the realization of a novel technology platform for an alternative computing paradigm.

Numerical investigation of an all-optical logic OR gate at 80 Gb/s with a dual pump–probe semiconductor optical amplifier (SOA)-assisted Mach–Zehnder interferometer (MZI)

The performance of an all-optical OR gate using a dual pump–probe semiconductor optical amplifier (SOA)-assisted Mach–Zehnder interferometer (MZI) is investigated and demonstrated through numerical simulations at a data rate of 80 Gb/s. The proposed scheme enables to obtain a higher quality factor and smaller pattern dependence for a more feasible choice of critical operating parameters than when using for the same purpose the SOA–delayed interferometer.

A Multifunctional Molecular Probe for Detecting Hg2+ and Ag⁺ Based on Ion-Mediated Base Mismatch.

In this paper, a multifunctional biosensing platform for sensitively detecting Hg2+ and Ag+, based on ion-mediated base mismatch, fluorescent labeling, and strand displacement, is introduced. The sensor can also be used as an OR logic gate, the multifunctional design of sensors is realized. Firstly, orthogonal experiments with three factors and three levels were carried out on the designed sensor, and preliminary optimization of conditions was performed for subsequent experiments. Next, the designed sensor was tested the specificity and target selectivity under the optimized conditions, and the application to actual environmental samples further verified the feasibility. Generally, this is a convenient, fast, stable, and low-cost method that provides a variety of ideas and an experimental basis for subsequent research.

Toehold integrated molecular beacon system for a versatile non-enzymatic application.

A molecular beacon (MB) is an oligonucleotide hybridization probe with a hairpin-shaped structure that leads to specific and instantaneous nucleic acid hybridization, enabling a variety of applications. However, integration of additional module sequences interferes with the performance of MBs and increases the complexity of sequence design. Herein, we develop and characterize a toehold integrated molecular beacon (ToMB) strategy for nucleic acid hybridization, where the reaction rate can be flexibly regulated by a target-induced MB conformational switch. Using this basic mechanism, the ToMB is capable of identifying nucleic acids with high specificity and a wider linearity range compared with the conventional molecular beacon system. We further applied the ToMB to the construction of a hybridization chain reaction system and a basic OR logic gate VJHto explore its programmability and versatility. Our results strongly suggest that the novel ToMB can act as a powerful nano-module to construct universal and multifunctional biosensors or molecular computations. Graphical abstract Molecular beacon is employed as a flexible and switchable spacer to control the toehold-mediated strand displacement reaction.

On/Off Fluorescent Chemosensor for Selective Detection of Divalent Iron and Copper Ions: Molecular Logic Operation and Protein Binding.

Here, naphthalene diamine-based β-diketone derivative (compound LH) was successfully used as a dual signaling probe for divalent cations, Fe2+ and Cu2+ ions, in bimodal methods (colorimetric and fluorometric). It showed fluorescent enhancement for Fe2+ ion by photoinduced electron transfer mechanism and fluorescence quenching for Cu2+ ion by charge-transfer process. Binding stoichiometry for [LH–(Fe2+)2] and [LH–(Cu2+)2] was found to be 1:2 by Job’s plot method and, the binding constants were calculated as 1.6638 × 1010 and 9.22929 × 108 M–1, respectively. Compound LH exhibited OR and XOR logic gate behavior with H+, Fe2+, and Cu2+ as inputs. Further, the compound LH and bovine serum albumin binding interaction showed quenching of fluorescence by Förster resonance energy-transfer mechanism.

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.

DNA colorimetric logic gate in microfluidic chip based on unmodified gold nanoparticles and molecular recognition

Small molecules have been widely developed as drugs, dyes, and research tools. DNA logic system interaction with small molecules as a new analytical method has offered remarkable promise for disease diagnosis and therapy. However, tedious modification process and large sample consumption of traditional DNA logic gates limit the application of this method in bioanalysis. Therefore, developing a simple and less sample consumption platform for DNA logic gates construction is of great importance. Here, we proposed a DNA colorimetric multilevel circuit construction strategy using gold nanoparticles (AuNPs) as an indicator without any modification and labeling step. Two colorimetric logic gates were constructed based on the aggregation of AuNPs mediated by molecular recognition between DNA and protoberberines (palmatine/berberine), including a NIMPLY logic gate and a multi-input NIMPLY + OR logic gate. The logic gate allows the detection of DNA concentrations as low as 0.25 μg/mL by naked eyes within 10 min. More importantly, a microfluidic device was successfully designed to perform the DNA molecular logic gates for reducing reagent consumption and performing precisely and automatically. The working volume of the logic system has been successfully reduced from 0.5 mL in bulk to 22 μL in our designed microfluidic chip, and the DNA solution needed was only 1.1 μL. The method presented here showed great potential in bioanalysis, diagnostics and therapeutics.

Graphene oxide/silver nanoclusters based logic devices and their application to multiplexed analysis of miRNA

Molecular-level logic gates have drawn increasing attention in nonarithmetic information processing, data transmission, logic computation and multiplexed analysis. Based on the characteristic of the graphene oxide (GO) and DNA-stabilized silver nanoclusters (AgNCs), a simple and universal platform is developed for integration of multiple logic gates to achieve parity generator and parity checker functions. The parity generator/checker can detect the inevitable bit errors during any type of binary data transmission. Moreover, the GO/AgNCs platform has the ability to construct analog OR and INHIBIT logic gates. And the integration of OR and INHIBIT logic gates provide an interesting approach for distinguishing multiple target miRNAs, presenting great application in development of rapid and intelligent detection. The function of a parity generator/checker and advanced sensor has been realized with fluorescent molecular switches taking advantage of the efficient adsorption/quenching ability of GO toward AgNCs, preventing laborious modification of biomolecules. Furthermore, as the fluorescence quencher consists of biocompatible nanomaterials, the devices can stably perform their logic operations in a biological matrix, which holds great potential application in future clinical diagnosis.

Harnessing energy-sharing collisions of Manakov solitons to implement universal NOR and OR logic gates.

The energy-sharing collision of bright optical solitons in the Manakov system, governing pulse propagation in high birefringent fiber, is employed theoretically to realize optical logic gates. In particular, we successfully construct (theoretically) the universal NOR gate and the OR gate from the energy-sharing collisions of just four bright solitons which can be well described by the exact bright four-soliton solution of the Manakov system. This construction procedure has important merits such as realizing the two input gates with a minimal number of soliton collisions and possibilities of multistate logic. The recent experiments on Manakov solitons suggest the possibility of implementation of this theoretical construction of such gates and ultimately an all-optical computer.

A BODIPY derivative for colorimetric fluorescence sensing of Hg2+, Pb2+ and Cu2+ ions and its application in logic gates

A BODIPY-based colorimetric and fluorescent chemosensor 1 anchored with dipyridylamino (DPA) receptor has been designed, synthesized and characterized. It exhibited a simultaneous sensitive recognition for Cu2+, Hg2+ and Pb2+ ions. With the addition of these three kinds of metal ions into 1 in CH3CN, its initial absorption maximum displayed obvious blue shifts, and the color changes of the solution could be clearly observed by naked eyes. Besides, the fluorescence intensity was significantly enhanced accompanied with the appearance of new emission peaks at 587 nm for Pb2+ and Hg2+ ions and 545 nm for Cu2+ ions. These results were attributed to the π-deconjugation between N-pyridyl and the BODIPY group due to the binding of metal ions with the BODIPY and DPA groups. Based on the sensing behaviors of 1, three logic gates (OR, INHIBT and combinational logic gate) were constructed correspondingly.

All Optical Logic Gates Using Hybrid Metal Insulator Metal Plasmonic Waveguide

In this letter, all optical logic gates (OR, XOR, and NOT), based on hybrid metal insulator metal (HMIM) plasmonic waveguide (Ag-SiO2-Si-SiO2-Ag) have been proposed and designed in the confinement area of $0.25\times 0.04\,\,\mu \text{m}^{2}$ at $1.55~\mu \text{m}$ operating wavelength. The proposed logic gates work on principle of linear interference, are designed using Y-splitter. OR and XOR logic gates are designed in footprint area of 17.12 and $19.6~\mu \text{m}^{2}$ , respectively, which is several times miniaturized compared to previous reports. Moreover an intensity contrast ratio of 26 dB has been achieved between ON and OFF states for XOR and NOT logic gates, which is 3 to 4 fold enhanced compared with previous literature. This study opens a new avenue for designing of chip scale plasmonic integrated circuits.

The Design of a Single-Bit CMOS Image Sensor for Iris Recognition Applications.

This paper presents a single-bit CMOS image sensor (CIS) that uses a data processing technique with an edge detection block for simple iris segmentation. In order to recognize the iris image, the image sensor conventionally captures high-resolution image data in digital code, extracts the iris data, and then compares it with a reference image through a recognition algorithm. However, in this case, the frame rate decreases by the time required for digital signal conversion of multi-bit digital data through the analog-to-digital converter (ADC) in the CIS. In order to reduce the overall processing time as well as the power consumption, we propose a data processing technique with an exclusive OR (XOR) logic gate to obtain single-bit and edge detection image data instead of multi-bit image data through the ADC. In addition, we propose a logarithmic counter to efficiently measure single-bit image data that can be applied to the iris recognition algorithm. The effective area of the proposed single-bit image sensor (174 × 144 pixel) is 2.84 mm2 with a 0.18 μm 1-poly 4-metal CMOS image sensor process. The power consumption of the proposed single-bit CIS is 2.8 mW with a 3.3 V of supply voltage and 520 frame/s of the maximum frame rates. The error rate of the ADC is 0.24 least significant bit (LSB) on an 8-bit ADC basis at a 50 MHz sampling frequency.

Autonomous DNA nanomachine based on cascade amplification of strand displacement and DNA walker for detection of multiple DNAs

DNA can be modified to function as a scaffold for the construction of a DNA nanomachine, which can then be used in analytical applications if the DNA nanomachine can be triggered by the presence of a diagnostic DNA or some other analyte. We herein propose a novel and powerful DNA nanomachine that can detect DNA via combining the tandem strand displacement reactions and a DNA walker. Three different DNA sensing platforms are described, where the whole DNA machine was constructed on a gold electrode (GE). This cascade multiple amplification strategy exhibited an excellent sensitivity. Under optimal conditions, the electrochemical sensor could achieve a detection limit of 36 fM with a linear range from 50 to 500 fM. In particular, the electrochemical sensor could easily distinguish the base mutations. More interestingly, the DNA nanomachine could be used to construct analog AND and OR logic gates. We demonstrate that electrochemical signals generated from the different input combinations can be used to distinguish multiple target DNAs. The practical applicability of the present biosensor is demonstrated by the detection of target DNA in human serum with satisfactory results, which holds great potential for a future application in clinical diagnosis.

A sequence-activated AND logic dual-channel fluorescent probe for tracking programmable drug release.

The translation of biomarker sensing into programmable diagnostics or therapeutic applications in vivo is greatly challenging, especially for eliminating the 'false positive' signals from OR logic gates. Herein we present a sense-of-logic dual-channel nanoprobe, operating through a sequence-activated AND logic gate by responding ultra-sensitively to pH changes and being subsequently triggered with biothiol for the controllable release of anti-cancer drugs. Specifically, programmable drug release is conducted in a multistage tumor microenvironment (acidic endocytic organelles followed by abnormal glutathione-overexpressing cell cytosol), which is synchronous with dual-channel near-infrared (NIR) fluorescence output. This approach represents the merging of sensing and release, including logically enabled molecular design, biomarker sensing, and controllable drug release. Impressively, the sequential AND logic feature within an unprecedented framework provides feedback on the diversity and complexity of biological milieu, along with remarkably enhancing the tumor therapeutic efficiency via its precise targeting ability and programmable drug release.

Allosteric pyruvate kinase-based \u201clogic gate\u201d synergistically senses energy and sugar levels in Mycobacterium tuberculosis

Pyruvate kinase (PYK) is an essential glycolytic enzyme that controls glycolytic flux and is critical for ATP production in all organisms, with tight regulation by multiple metabolites. Yet the allosteric mechanisms governing PYK activity in bacterial pathogens are poorly understood. Here we report biochemical, structural and metabolomic evidence that Mycobacterium tuberculosis (Mtb) PYK uses AMP and glucose-6-phosphate (G6P) as synergistic allosteric activators that function as a molecular “OR logic gate” to tightly regulate energy and glucose metabolism. G6P was found to bind to a previously unknown site adjacent to the canonical site for AMP. Kinetic data and structural network analysis further show that AMP and G6P work synergistically as allosteric activators. Importantly, metabolome profiling in the Mtb surrogate, Mycobacterium bovis BCG, reveals significant changes in AMP and G6P levels during nutrient deprivation, which provides insights into how a PYK OR gate would function during the stress of Mtb infection.

Fully inkjet-printed two-dimensional material field-effect heterojunctions for wearable and textile electronics

Fully printed wearable electronics based on two-dimensional (2D) material heterojunction structures also known as heterostructures, such as field-effect transistors, require robust and reproducible printed multi-layer stacks consisting of active channel, dielectric and conductive contact layers. Solution processing of graphite and other layered materials provides low-cost inks enabling printed electronic devices, for example by inkjet printing. However, the limited quality of the 2D-material inks, the complexity of the layered arrangement, and the lack of a dielectric 2D-material ink able to operate at room temperature, under strain and after several washing cycles has impeded the fabrication of electronic devices on textile with fully printed 2D heterostructures. Here we demonstrate fully inkjet-printed 2D-material active heterostructures with graphene and hexagonal-boron nitride (h-BN) inks, and use them to fabricate all inkjet-printed flexible and washable field-effect transistors on textile, reaching a field-effect mobility of ~91 cm2 V−1 s−1, at low voltage (<5 V). This enables fully inkjet-printed electronic circuits, such as reprogrammable volatile memory cells, complementary inverters and OR logic gates.