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The application of spin–orbit torque (SOT) devices to neuromorphic computing platforms is focused on the development of hardware circuit architectures. However, the inter-device variability, the integration modes of devices and peripheral circuits, and appropriate application scenarios are still unclear, limiting the development of SOT devices in neuromorphic computing. To solve this problem, this paper first proposes a circuit compensation scheme for the difference in resistance values of SOT devices, which solves this variability problem at the circuit level. Moreover, a synergistic scheme with the circuit is developed based on the correspondence between the multistate resistance characteristics of the SOT devices and a convolutional algorithm. To achieve this, a multichannel SOT convolutional kernel circuit architecture is built, which implements an image edge recognition application. Finally, based on a simulation model, an image edge recognition hardware circuit based on our CoPt-SOT devices is implemented, which is capable of performing image edge recognition with an accuracy of 96.33%. This scheme provides technical support and development prospects for SOT devices in neural network hardware applications. [ABSTRACT FROM AUTHOR]

CO2 laser machining is a cost effective and time saving solution for fabricating microchannels on polymethylmethacrylate (PMMA). Due to the lack of research on the incubation effect and ablation behavior of PMMA under high-power laser irradiation, predictions of the microchannel profile are limited. In this study, the ablation process and mechanism of a continuous CO2 laser machining process on microchannel production in PMMA in single-pass and multi-pass laser scan modes are investigated. It is found that a higher laser energy density of a single pass causes a lower ablation threshold. The ablated surface can be divided into three regions: the ablation zone, the incubation zone, and the virgin zone. The PMMA ablation process is mainly attributed to the thermal decomposition reactions and the splashing of molten polymer. The depth, width, aspect ratio, volume ablation rate, and mass ablation rate of the channel increase as the laser scanning speed decreases and the number of laser scans increases. The differences in ablation results obtained under the same total laser energy density using different scan modes are attributed to the incubation effect, which is caused by the thermal deposition of laser energy in the polymer. Finally, an optimized simulation model that is used to solve the problem of a channel width greater than spot diameter is proposed. The error percentage between the experimental and simulation results varies from 0.44% to 5.9%. [ABSTRACT FROM AUTHOR]

Recent progress in two-dimensional ferroelectrics greatly expands the versatility and tunability in van der Waals heterostructure based electronics. However, the switching endurance issue that widely plagues conventional ferroelectrics in practical applications is hitherto unexplored for van der Waals layered ferroelectrics. Herein, we report the observation of unusual polarization fatigue behaviors in van der Waals layered CuInP2S6, which also possesses finite ionic conductivity at room temperature. The strong intertwinement of the short-range polarization switching and long-range ionic movement in conjunction with the van der Waals layered structure gives rise to unique morphological and polarization evolutions under repetitive electric cycles. With the help of concerted chemical, structural, lattice vibrational and dielectric analyses, we unravel the critical role of the synergy of ionic migration and surface oxidation on the anomalous polarization enhancement and the eventual polarization degradation. This work provides a general insight into the polarization fatigue characteristics in ionically-active van der Waals ferroelectrics and delivers potential solutions for the realization of fatigue-free capacitors. The authors find unconventional fatigue characteristics, involving dramatic morphological changes and anomalous polarization enhancement in van der Waals layered ferroelectric CuInP2S6, due to a synergic effect of ionic conduction and surface oxidation. [ABSTRACT FROM AUTHOR]

The discovery of layered magnetic semiconductor materials has stimulated a search for the magnetic order of atomically thin‐layered materials. However, layer‐controlled growth is difficult because of the high nucleation barrier of the material surface during the few‐layer formation of 2D materials. Herein, a seeding solution method is demonstrated that changes the nucleation mode of seed crystals on the substrate surface by precisely controlling the concentration of metal precursors and promoting the formation of cluster seed nuclei to ensure a sufficient source of metal for subsequent reactions. It is studied that the kinetic and thermodynamic synergy through temperature control is readily to grow VS2 with a tunable layer number. Monolayer VS2 exhibits strong ferromagnetic ordering with a saturation magnetization strength (Ms) of 37 emu per cc and a coercivity (Hc) of 135 Oe at 300 K. Notably, the ferromagnetism of VS2 has layer‐dependent performance of the saturation magnetization and coercivity decreases with increasing number of layers. Monolayer VS2 exhibits typical semiconductor properties in Hall devices. This study broadens the chemical pathway for the tunable synthesis of 2D layered magnetic materials and provides the possibility for the construction of novel spintronic and magnetoelectronic devices. [ABSTRACT FROM AUTHOR]