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Owing to programmable nonlinear dynamics, magnetic domain wall (DW)‐based devices can be configured to function as spintronic neurons, promising to execute sophisticated tasks as a human brain. Developing energy‐efficient, CMOS compatible, reliable, and tunable spintronic neurons to emulate brain‐inspired processes has been a key research goal for decades. Here, a new type of DW device is reported with biological neuron characteristics driven by the synergistic interaction between spin‐orbit torque and built‐in field (Hbuilt‐in) in magnetic tunnel junctions, enabling time‐ and energy‐efficient leaky‐integrate‐and‐fire and self‐reset neuromorphic implementations. A tilted magnetic anisotropic free layer is proposed and further executed to mitigate the DW retrograde motion by suppressing the Walker breakdown. Complementary experiments and micromagnetic co‐simulation results show that the integrating/leaking time of the developed spintronic neuron can be tuned to 12/15 ns with an integrating power consumption of 65 µW, which is 36× and 1.84× time and energy efficient than the state‐of‐the‐art alternatives, respectively. Moreover, the spatial distribution of Hbuilt‐in can be modulated by adjusting the width and compensation of the reference layer, facilitating tunable activation function generator exploration. Such architecture demonstrates great potential in both fundamental research and new trajectories of technology advancement for spintronic neuron hardware applications. [ABSTRACT FROM AUTHOR]

The nanoscale electrical and mechanical properties in the CdTe thin films solar cells were investigated using the scanning probe microscopy. The comparative localized electrical and mechanical properties between as-grown and CdCl2 treated CdTe thin films for the grain and grain boundaries were studied using the conductive atomic force microscopy (cAFM) and force modulation microscopy (FMM). An increased electrical behavior and decreased elastic stiffness in the CdCl2 treated thin films were recorded to elucidate the impact from the grain growth of CdTe grains. On applying a simulated working electrical bias into the CdTe thin-film solar cells, the electric field across the CdTe film can increase the softness of CdTe thin film. The results imply the presence of a potential mechanical failure site in the CdTe grain boundary, which may lead to device degradation. [ABSTRACT FROM AUTHOR]

B Spintronic Neurons b Spintronic neuron hardware explorations arouse a new surge of breakthroughs in neuromorphic computing. The developed magnetic domain wall devices demonstrate biological neuron characteristics driven by the synergistic interaction between spin-orbit torque and built-in field in magnetic tunnel junctions, facilitating a new trajectory of time- and energy-efficient leaky-integrate-fire-self-reset neurons implementation. Synergy of Spin-Orbit Torque and Built-In Field in Magnetic Tunnel Junctions with Tilted Magnetic Anisotropy: Toward Tunable and Reliable Spintronic Neurons (Adv. Sci. 30/2022). [Extracted from the article]

Abstract: ZnO nanowires were grown on Au-coated Si (100) substrates by the method of vapor–liquid–solid (VLS) growth processing technique. The effects of supply time of Ar gas current on morphology and microstructure of Au-catalyzed ZnO nanowires were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy. The results showed that the morphologies of ZnO nanostructures strongly depended on the time of flowing Ar gas. When the time of flowing Ar gas was 90s, ZnO showed nanowires with hexagonal structure. Their diameters and lengths were 160nm and 20μm, respectively, on average, and the Raman scattering peak located at 438cm−1 reached maximum intensity. The results also showed that the ZnO growth could be patterned by controlling the initial position of Au-coated area on the Si substrates. [Copyright &y& Elsevier]

• The nanoreactor is obtained by the microwave-assisted surface imprinting technique. • Heterojunction formed between PEDOT and CdS improves the photocatalytic activity. • Fe 3 O 4 transfers photogenerated e- and further enhances the photocatalytic activity. • Imprinted cavity specifically adsorbs DM and improves the selectivity of nanoreactor. • PEDOT imprinted layer inhibites CdS photocorrosion and its secondary pollution. Magnetic imprinted PEDOT/CdS heterojunction photocatalytic nanoreactors are synergistically synthesized by the microwave-assisted surface imprinting technique. The coating of the PEDOT imprinted layer is conducive to the three-dimensional (3D) specific recognition and selective photocatalysis of danofloxacin mesylate due to the formation of imprinted cavities. The representative specific degradation selectivity coefficient of the developed nanoreactor relative to CdS/Fe 3 O 4 /HNT and magnetic non-imprinted PEDOT/CdS heterojunction is 2.08 and 2.11, respectively, clearly elaborating the excellent selectivity. The introduction of Fe 3 O 4 into PEDOT/CdS heterojunction enhances the transfer of photoexcited electrons, thereby, the photocatalytic activity has been significantly boosted up to ∼84.84 %. Meanwhile, the existence of PEDOT imprinted layer not only extracts the photoinduced holes produced by CdS, but also encapsulates CdS, which effectively inhibits the CdS photocorrosion and hinders its secondary pollution. With the improved selectivity and photocatalytic activity, our work paves the way to efficiently remove the target pollutant aiming at the practical application requirements. [ABSTRACT FROM AUTHOR]

Eu2+-activated Ba 5 SiO 4 Cl 6 phosphors with blue and green emissions were synthesized by a solid-state reaction route in a reduction atmosphere. The obtained crystal structure and photoluminescent properties indicated that three various Ba2+ ions sites were partially occupied by the Eu2+ ions. The optimal doping content for Eu2+ ions in the Ba 5 SiO 4 Cl 6 system was 5 mol%. The electric dipole-dipole interaction was attributed to the involved concentration quenching effect. The thermal resistance performance was identified by using the temperature-dependent emission spectra. Importantly, the internal quantum efficiency of the established final products reached up to 50.8%. Through utilizing the diverse sensitivities of blue and green emissions from Eu2+ ions to the temperature, a neoteric optical thermometer with a high absolute and relative sensor sensitivity of 0.031 K-1 and 0.87% K−1, respectively, at 498 K was achieved. By integrating the resultant cyan phosphors, commercial CaAlSiN 3 :Eu2+ red phosphors and a near-ultraviolet chip, the warm white light-emitting diodes with admirable colorific properties were integrated and manufactured. The complementary results elaborate that the Eu2+-activated Ba 5 SiO 4 Cl 6 phosphors are bifunctional platforms for both optical thermometer and indoor illumination. • The resultant phosphors exhibited visible cyan emission when excited at 397 nm. • The dipole-dipole interaction contributed to the concentration quenching mechanism. • The resultant phosphors possessed good thermal stability and high quantum efficiency. • The Sa and Sr values of the products was 0.031 K−1 and. • The LED lamp emitted brightness white light with superior photoelectric properties. [ABSTRACT FROM AUTHOR]