Parallel Logic Operations in Electrically Tunable Two-Dimensional Homojunctions.

Two-dimensional materials show great potential for future electronics beyond silicon materials. Here, we report an exotic multiple-port device based on multiple electrically tunable planar p-n homojunctions formed in a two-dimensional (2D) ambipolar semiconductor, tungsten diselenide (WSe2). In this device, we prepare multiple gates consisting of a global gate and several local gates, by which electrostatically induced holes and electrons are simultaneously accumulated in a WSe2 channel, and furthermore, at the boundaries, p-n junctions are formed as directly visualized by Kelvin probe force microscopy. Therefore, in addition to the gate voltages in our device, the drain/source bias can also be used to switch the 2D WSe2 channel on/off due to the rectification effect of the formed p-n junctions. More importantly, when the voltage on the global gate electrode is altered, all p-n junctions are affected, which makes it possible to perform parallel logic operations.

Bi-Directional and Operand-Controllable In-Memory Computing for Boolean Logic and Search Operations with Row and Column Directional SRAM (RC-SRAM).

The von Neumann architecture is no longer sufficient for handling large-scale data. In-memory computing has emerged as the potent method for breaking through the memory bottleneck. A new 10T SRAM bitcell with row and column control lines called RC-SRAM is proposed in this article. The architecture based on RC-SRAM can achieve bi-directional and operand-controllable logic-in-memory and search operations through different signal configurations, which can comprehensively respond to various occasions and needs. Moreover, we propose threshold-controlled logic gates for sensing, which effectively reduces the circuit area and improves accuracy. We validate the RC-SRAM with a 28 nm CMOS technology, and the results show that the circuits are not only full featured and flexible for customization but also have a significant increase in the working frequency. At VDD = 0.9 V and T = 25 °C, the bi-directional search frequency is up to 775 MHz and 567 MHz, and the speeds for row and column Boolean logic reach 759 MHz and 683 MHz.

Printed On-Chip Perovskite Heterostructure Arrays for Optical Switchable Logic Gates.

The use of optoelectronic devices for high-speed and low-power data transmission and computing is considered in the next-generation logic circuits. Heterostructures, which can generate and transmit photoresponse signals dealing with different input lights, are highly desirable for optoelectronic logic gates. Here, the printed on-chip perovskite heterostructures are demonstrated to achieve optical-controlled "AND" and "OR" optoelectronic logic gates. Perovskite heterostructures are printed with a high degree of control over composition, site, and crystallization. Different regions of the printed perovskite heterostructures exhibit distinguishable photoresponse to varied wavelengths of input lights, which can be utilized to achieve optical-controlled logic functions. Correspondingly, parallel operations of the two logic gates ("AND" and "OR") by way of choosing the output electrodes under the single perovskite heterostructure. Benefiting from the uniform crystallization and strict alignment of the printed perovskite heterostructures, the integrated 3 × 3 pixels all exhibit 100% logic operation accuracy. Finally, optical-controlled logic gates responding to multiwavelength light can be printed on the predesigned microelectrodes as the on-chip integrated circuits. This printing strategy allows for integrating heterostructure-based optical and electronic devices from a unit-scale device to a system-scale device.

Switchable Two-Dimensional AND and Exclusive OR Operation Based on Dual-Wavelength Metasurfaces.

Logic operation serves as the foundation and core element of computing networks; it will bring huge vitality to advanced information processing with its adaptation in the optical domain. As fundamental logic operations, AND and exclusive OR (XOR) operations serve a multitude of purposes, such as their ability to cooperate in enabling image processing and interpretation. Here, we propose and experimentally demonstrate a wavelength multiplexed AND and XOR function based on metasurfaces. By combining two cosine gratings with distinct frequencies and an initial phase difference of π/2, we extract the similarities and differences between two input images simultaneously by illuminating them with 445 and 633 nm wavelengths. Additionally, we explore its potential in information encryption, where overall security is enhanced by distributing distinct parts of initial information and encoded keys to different receivers. This design possesses the benefits of convenient mode switching and high-quality imaging, facilitating advanced applications in pattern recognition, machine vision, medical diagnosis, etc.

Stochastic power processing through logic operation of power packets.

This article presents an application of the recently proposed logic operation of power based on power packetization. In a power packet despatching system, the power supply can be considered as a sequence of power pulses, where the occurrence of pulses follows a probability that corresponds to the capacity of the power sources or power lines. In this study, we propose a processing scheme to reshape a stream of power packets from such stochastic sequences to satisfy the load demand. The proposed scheme is realized by extending the concept of stochastic computing to the power domain. We demonstrate the operation of the proposed scheme through experiments and numerical simulations by implementing it as a function of a power packet router, which forms a power packet despatching network. The stochastic framework proposed in this study provides a new design foundation for low-power distribution networks as an embodiment of the close connection between the cyber and physical components.

The Amplified DNA Logic Gates Based on Aptamer-Receptor Recognition for Cell Detection and Bioimaging.

A powerful and accurate method for identifying and isolating cells would be of great importance due to its sensitivity, gentleness and effectiveness. Here, we designed a receptor-based DNA logic device that allows Boolean logic analysis of multiple cells. For ease of expression, the molecules on the cell surface that can bind to the aptamer are referred to as "receptors". This DNA logic device sends signals based on cell surface sgc8c and sgc4f receptor expression by performing NOT, NOR, AND and OR logic operations, and amplifies and evaluates the signals using HCR. Meanwhile, the release of ICG from the endopore of HMSNs is controlled by affecting structural changes in the DNA logic device. This approach can accurately identify and treat multiple cells on demand based on the presence or absence of cell-specific receptors, facilitating the development of personalized medicine.

High-Performance Neuromorphic Computing and Logic Operation Based on a Self-Assembled Vertically Aligned Nanocomposite SrTiO3:MgO Film Memristor.

Neuromorphic computing based on memristors capable of in-memory computing is promising to break the energy and efficiency bottleneck of well-known von Neumann architectures. However, unstable and nonlinear conductance updates compromise the recognition accuracy and block the integration of neural network hardware. To this end, we present a highly stable memristor with self-assembled vertically aligned nanocomposite (VAN) SrTiO3:MgO films that achieve excellent resistive switching with low set/reset voltage variability (4.7%/-5.6%) and highly linear conductivity variation (nonlinearity = 0.34) by spatially limiting the conductive channels at the vertical interfaces. Various synaptic behaviors are simulated by continuously modulating the conductance. Especially, convolutional image processing using diverse crossbar kernels is demonstrated, and the artificial neural network achieves an overwhelming recognition accuracy of up to 97.50% for handwritten digits. Even under the perturbation of Poisson noise (λ = 10), 6% Salt and Pepper noise, and 5% Gaussian noise, the high recognition accuracies are retained at 95.43%, 94.56%, and 95.97%, respectively. Importantly, the logic memory function is proven experimentally based on the nonvolatile properties. This work provides a material system and design idea to achieve high-performance neuromorphic computing and logic operation.

Low-Voltage Solution-Processed Zinc-Doped CuI Thin Film Transistors with NOR Logic and Artificial Synaptic Function.

Low-voltage Zn-doped CuI thin film transistors (TFTs) gated by chitosan dielectric were fabricated at a low temperature. The Zn-doped CuI TFT exhibited a more superior on/off current ratio than CuI TFT due to the substitution or supplementation of copper vacancies by Zn ions. The Zn-doped CuI films were characterized by scanning electron microscope, X-ray diffraction, and X-ray photoelectron spectroscopy. The Zn-doped CuI TFTs exhibited an on/off current ratio of 1.58 × 104, a subthreshold swing of 70 mV/decade, and a field effect mobility of 0.40 cm2V-1s-1, demonstrating good operational stability. Due to the electric-double-layer (EDL) effect and high specific capacitance (17.3 µF/cm2) of chitosan gate dielectric, Zn-doped CuI TFT operates at a voltage below -2 V. The threshold voltage is -0.2 V. In particular, we have prepared Zn-doped CuI TFTs with two in-plane gates and NOR logic operation is implemented on such TFTs. In addition, using the ion relaxation effect and EDL effect of chitosan film, a simple pain neuron simulation is realized on such a p-type TFTs for the first time through the bottom gate to regulate the carrier transport of the channel. This p-type device has promising applications in low-cost electronic devices, complementary electronic circuit, and biosensors.

Optical Logic Gates Excited by a Gauss Vortex Interference Beam Based on Spatial Self-Phase Modulation in 2D MoS2.

Vortex beams with optical orbital angular momentum have broad prospects in future high-speed and large-capacity optical communication. In this investigation of materials science, we found that low-dimensional materials have feasibility and reliability in the development of optical logic gates in all-optical signal processing and computing technology. We found that spatial self-phase modulation patterns through the MoS2 dispersions can be modulated by the initial intensity, phase, and topological charge of a Gauss vortex superposition interference beam. We utilized these three degrees of freedom as the input signals of the optical logic gate, and the intensity of a selected checkpoint on spatial self-phase modulation patterns as the output signal. By setting appropriate thresholds as logic codes 0 and 1, two sets of novel optical logic gates, including AND, OR, and NOT gates, were implemented. These optical logic gates are expected to have great potential in optical logic operations, all-optical networks, and all-optical signal processing.

A Biocompatible Supercapacitor Diode with Enhanced Rectification Capability toward Ion/Electron-Coupling Logic Operations.

The main challenge faced by the forthcoming human-computer interaction is that biological systems and electronic devices adopt two different information carriers, i.e., ions and electrons, respectively. To bridge the gap between these two systems, developing ion/electron-coupling devices for logic operation is a feasible and effective approach. Accordingly, herein a supercapacitor-based ionic diode (CAPode) that takes electrochemically amorphized molybdenum oxide as the working electrode is developed. Benefiting from its unique size and charge dual ion-sieving effects, the molybdenum oxide electrode exhibits a record-high rectification ratio of 136, which is over 10 times higher than those of reported systems. It also delivers an ultrahigh specific capacitance of 448 F g⁻1 and an excellent cycling stability of up to 20 000 cycles, greatly outperforming those of previous works. These excellent rectification capability and electrochemical performances allow the as-built CAPode to work well in AND and OR logic gates, validating great potential in ion/electron-coupling logic operations. More attractively, the superior biocompatibilities of molybdenum oxide and relevant constituent materials enable the constructed CAPode to be applied as bioelectronics without regard to biosafety, paving a new way toward forthcoming human-computer interaction.

Closed Cyclic DNA Machine for Sensitive Logic Operation and APE1 Detection.

DNA self-assembly has been developed as a kind of robust signal amplification strategy, but most of reported assembly pathways are programmed to amplify signal in one direction. Herein, based on mutual-activated cascade cycle of hybridization chain reaction (HCR) and catalytic hairpin assembly (CHA), a closed cycle circuit (CCC) based DNA machine is developed for sensitive logic operation and molecular recognition. Benefiting from the synergistically accelerated signal amplification, the closed cyclic DNA machine enabled the logic computing with strong and significant output signals even at weak input signals. The typical logic operations such as OR, YES, AND, INHIBIT, NOR, and NAND gate, are conveniently and clearly executed with this DNA machine through rational design of the input and computing elements. Moreover, by integrating the target recognition module with the CCC module, the proposed DNA machine is further employed in the homogeneous detection of apurinic/apyrimidinic endonuclease 1 (APE1). The precise recognition and exponential signal amplification facilitated the highly selective and sensitive detection of APE1 with limit of detection (LOD) of 7.8 × 10-5 U mL-1 . Besides, the normal cells and tumor cells are distinguished unambiguously by this method according to the detected concentration difference of cellular APE1, which indicates the robustness and practicability of this method.

Colorimetric detection of viral RNA fragments based on an integrated logic-operated three-dimensional DNA walker.

Timely and accurate detection of virus is crucial for preventing spread of disease and early treatment of the infected cases. Herein we design an integrated logic-operated three-dimensional DNA walker for colorimetric detection of viral RNA fragments, by taking SARS-CoV-2 as an example. The DNA walker is composed of small amounts of dually-blocked walking strands and large amounts of dual-stem-loop track strands on gold nanoparticles. The walking strand contains a swing arm domain and a DNAzyme domain blocked at both sides of catalytic core, while the track strand contains a substrate domain located at the peripheral larger loop. Only the presence of both ORF1ab and N RNA fragments can fully de-block the walking strand, which then continuously hybridizes with track strands and cleaves them by DNAzyme-catalyzed hydrolysis. As the cleavage of track strands from long-stranded, double stem-loop structure to short-stranded, linear sequence, the DNA walker shows much lowered stability due to decreased negative charge density and diminished steric repulsion, which then gets aggregated at high salt concentration, accompanied by a visible color change. The colorimetric DNA walker detects RNA fragments down to 1 nM, responds dual viral genes in a "AND" logic way, and shows high specificity to target sequence. It can further detect large nucleic acids containing ORF1ab and N sequences, and reach 200 copies/mL detection limit by coupling a simple upstream amplification of sample. The method may provide a convenient way for reliable detection of viral RNA.

A new hybrid Artificial Intelligence (AI) approach for hydro energy sites selection and integration.

The increase of energy demand in this era leads exploration of new renewable energy sites. Renewable energy offers multiple benefits; hence it is suitable to be harnessed to meet power needs. In Sarawak, exploitation of hydro energy is a very feasible potential due to the abundant river flows and high rainfall volume. Thus, in this paper, 155 potential Hydro Energy Sites (HES) are identified and divided into six districts using a raw and unprocessed data provided by Sarawak Energy Berhad (SEB). Since there are no similar researches previously done for identification and integration of hydro energy sources, in this paper, two stage complex data management was built using 155 HES locations in Sarawak. New spatial mapping technique were used for the first stage. From the new spatial mapping technique, the mapped data were categorized into groups, analysed and created new accurate mapping locations on the Sarawak map in terms of the districts using GIS Spatial tools. Their exact geographical locations were identified, and their coordinate systems have been retrieved as complete final data with geo-referencing technique in QGIS with ID numbers. Moreover, the power capacity of each location of all the 155 HES was quantified. By employing this data, the identified locations have been integrated into the already created 155 HES sites. For the second stage, a new two-part AI hybrid approach has been proposed and applied to improve optimal transmission line routing for each district to locate transmission line paths. The first part of hybrid AI implemented in this paper was TSP-GA and second part implemented in this paper was based on improved fuzzy logic with TSP-GA together. To ensure the optimal results are reliably achieved, both first part of TSP-GA and second part of improved fuzzy TSP-GA are utilized to generate the transmission line routing. These two approaches are required to obtain the minimal values of total distance and total elevation difference of each HES. Based on the benchmarking results, fuzzy TSP-GA successfully improved 12.99% for Song district, 7.52% for Kapit district, 3.71% for Belaga district, 1.54% for Marudi district, 18.01% for Limbang district, 11.00% for Lawas district when comparing against the ordinary TSP-GA approach.

Voltage-Controlled Conversion from CDS to MDS in an Azobenzene-Based Organic Memristor for Information Storage and Logic Operations.

For organic memristors, non-zero-crossing current-voltage (I-V) curves are often observed, which can be attributed to capacitive effects. If the conversion between the capacitance-dominated state (CDS) and the memristance-dominated state (MDS) can be realized in a controllable manner, more device functions can be obtained. In this work, a two-terminal memristor using a common organic dye, azobenzene (AZB), as the active layer was prepared. It is found that as the applied voltage gradually increases, the device can transition from CDS to MDS. In the low voltage range (<1 V), the device is in CDS, and the capacitance is significantly increased by ∼104 compared to the theoretical value. In the high voltage range (>1 V), the device is in MDS, achieving an HRS (high resistance state)/LRS (low resistance state) resistance ratio of ∼104, and the logic operations are achieved. Through the analysis of the I-V curve, energy diagram of the materials, and computer simulation results, the mechanisms of CDS, MDS, and their conversion are proposed. This work provides an in-depth understanding of the working mechanism of organic memristors and demonstrates the potential of AZB-based organic memristors for information storage and logic display applications.

A Chimeric Conjugate of Antibody and Programmable DNA Nanoassembly Smartly Activates T Cells for Precise Cancer Cell Targeting.

Synthetically directing T-cells against tumors emerges as a promising strategy in immunotherapy, while it remains challenging to smartly engage T cells with tunable immune response. Herein, we report an intelligent molecular platform to engineer T-cell recognition for selective activation to potently kill cancer cells. To this end, we fabricated a hybrid conjugate that uses a click-type DNA-protein conjugation to equip the T cell-engaging antibody with two distinct programmable DNA nanoassemblies. By integrating multiple aptameric antigen-recognitions within a dynamic DNA circuit, we achieved combinatorial recognition of triple-antigens on cancer cells for selective T-cell activation after high-order logic operation. Moreover, by coupling a DNA nanostructure, we precisely defined the valence of the antigen-binding aptamers to tune avidity, realizing effective tumor elimination in vitro and in vivo. Together, we present a versatile and programmable strategy for synthetic immunotherapy.

Characterization of multiscale logic operations in the neural circuits.

Background: Ever since the seminal work by McCulloch and Pitts, the theory of neural computation and its philosophical foundation known as 'computationalism' have been central to brain-inspired artificial intelligence (AI) technologies. The present study describes neural dynamics and neural coding approaches to understand the mechanisms of neural computation. The primary focus is to characterize the multiscale nature of logic computations in the brain, which might occur at a single neuron level, between neighboring neurons via synaptic transmission, and at the neural circuit level. Results: For this, we begin the analysis with simple neuron models to account for basic Boolean logic operations at a single neuron level and then move on to the phenomenological neuron models to explain the neural computation from the viewpoints of neural dynamics and neural coding. The roles of synaptic transmission in neural computation are investigated using biologically realistic multi-compartment neuron models: two representative computational entities, CA1 pyramidal neuron in the hippocampus and Purkinje fiber in the cerebellum, are analyzed in the information-theoretic framework. We then construct two-dimensional mutual information maps, which demonstrate that the synaptic transmission can process not only basic AND/OR Boolean logic operations but also the linearly non-separable XOR function. Finally, we provide an overview of the evolutionary algorithm and discuss its benefits in automated neural circuit design for logic operations. Conclusions: This study provides a comprehensive perspective on the multiscale logic operations in the brain from both neural dynamics and neural coding viewpoints. It should thus be beneficial for understanding computational principles of the brain and may help design biologically plausible neuron models for AI devices.

Electric power processing using logic operation and error correction.

In this study, electric power is processed using the logic operation method and the error correction algorithms to meet load demand. Electric power was treated as the physical flow through the distribution network, which was governed by circuit configuration and efficiency. The hardware required to digitize or packetize electric power, which is called power packet router, was developed in this research work for low power distribution. It provides an opportunity for functional electric power dispatching while disregarding the power flow in the circuit. This study proposes a new design for the network, which makes the logic operation of electric power possible and provides an algorithm to correct the inaccuracies caused by dissipation and noise. Phase shift of the power supply network is resulted by implementing the introduced design.

A 1T2C FeCAP-Based In-Situ Bitwise X(N)OR Logic Operation with Two-Step Write-Back Circuit for Accelerating Compute-In-Memory.

Ferroelectric capacitors (FeCAPs) with high process compatibility, high reliability, ultra-low programming current and fast operation speed are promising candidates to traditional volatile and nonvolatile memory. In addition, they have great potential in the fields of storage, computing, and memory logic. Nevertheless, effective methods to realize logic and memory in FeCAP devices are still lacking. This study proposes a 1T2C FeCAP-based in situ bitwise X(N)OR logic based on a charge-sharing function. First, using the 1T2C structure and a two-step write-back circuit, the nondestructive reading is realized with less complexity than the previous work. Second, a method of two-line activation is used during the operation of X(N)OR. The verification results show that the speed, area and power consumption of the proposed 1T2C FeCAP-based bitwise logic operations are significantly improved.

Thermochromic Color Switching to Temperature Controlled Volatile Memory and Counter Operations with Metal-Organic Complexes and Hybrid Gels.

Temperature is often not considered as a precision stimulus for artificial chemical systems in contrast to the host-guest interactions related to many natural processes. Similarly, mimicking multi-state volatile memory operations using a single molecular system with temperature as a precision stimulus is highly laborious. Here we demonstrate how a mixture of iron(II) chloride and bipyridine can be used as a reversible color-to-colorless thermochromic switch and logic operators. The generality of the approach was illustrated using CoII and NiII salts that resulted in color-to-color transitions. DMSO gels of these systems, exhibited reversible opaque-transparency switching. More importantly, optically readable multi-state volatile memory with temperature as a precision input has been demonstrated. The stored data is volatile and is lost instantaneously upon withdrawal or change of temperature. Simultaneous read-out at multiple wavelengths results in single-input/multi-output sequential logic operations such as data accumulators (counters) leading to volatile memory states. The present system provides access to thermoresponsive materials wherein temperature can be used as a precision stimulus.

Scan and Unlock: A Programmable DNA Molecular Automaton for Cell-Selective Activation of Ligand-Based Signaling.

Selective modulation of ligand-receptor interaction is essential in targeted therapy. In this study, we design an intelligent "scan and unlock" DNA automaton (SUDA) system to equip a native protein-ligand with cell-identity recognition and receptor-mediated signaling in a cell-type-specific manner. Using embedded DNA-based chemical reaction networks (CRNs) on the cell surface, SUDA scans and evaluates molecular profiles of cell-surface proteins via Boolean logic circuits. Therefore, it achieves cell-specific signal modulation by quickly unlocking the protein-ligand in proximity to the target cell-surface to activate its cognate receptor. As a proof of concept, we non-genetically engineered hepatic growth factor (HGF) with distinct logic SUDAs to elicit target cell-specific HGF signaling and wound healing behaviors in multiple heterogeneous cell types. Furthermore, the versatility of the SUDA strategy was shown by engineering tumor necrotic factor-α (TNFα) to induce programmed cell death of target cell subpopulations through cell-specific modulation of TNFR1 signaling.