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After decades of efforts, some fundamental physics for electrical switching of magnetization is still missing. Here, we report the discovery of the long-range intralayer Dzyaloshinskii-Moriya interaction (DMI) effect, which is the chiral coupling of orthogonal magnetic domains within the same magnetic layer via the mediation of an adjacent heavy metal layer. The effective magnetic field of the long-range intralayer DMI on the perpendicular magnetization is out-of-plane and varies with the interfacial DMI constant, the applied in-plane magnetic fields, and the magnetic anisotropy distribution. Striking consequences of the effect include asymmetric current/field switching of perpendicular magnetization, hysteresis loop shift of perpendicular magnetization in the absence of in-plane direct current, and sharp in-plane magnetic field switching of perpendicular magnetization. Utilizing the intralayer DMI, we demonstrate programable, complete Boolean logic operations within a single spin-orbit torque device. These results will stimulate investigation of the long-range intralayer DMI effect in a variety of spintronic devices. The authors find a magnetization switching mechanism and the long-range intralayer Dzyaloshinskii-Moriya interaction effect, which enables asymmetric magnetization switching and complete Boolean logic operations.

Perpendicularly magnetized synthetic antiferromagnets (SAF), possessing low net magnetization and high thermal stability as well as easy reading and writing characteristics, have been intensively explored to replace the ferromagnetic free layers of magnetic tunnel junctions as the kernel of spintronic devices. So far, utilizing spin-orbit torque (SOT) to realize deterministic switching of perpendicular SAF have been reported while a large external magnetic field is typically needed to break the symmetry, making it impractical for applications. Here, combining theoretic analysis and experimental results, we report that the effective modulation of Dzyaloshinskii-Moriya interaction by the interfacial crystallinity between ferromagnets and adjacent heavy metals plays an important role in domain wall configurations. By adjusting the domain wall configuration between Bloch type and Néel type, we successfully demonstrate the field-free SOT-induced magnetization switching in [Co/Pd]/Ru/[Co/Pd] SAF devices constructed with a simple wedged structure. Our work provides a practical route for utilization of perpendicularly SAF in SOT devices and paves the way for magnetic memory devices with high density, low stray field, and low power consumption. Synthetic antiferromagnets (SAF), formed out of alternating layers of a ferromagnet with neutral spacer combine technologically appealing properties of both antiferromagnets and ferromagnets. Here, Chen et al demonstrate controlled switching of an SAF, without the need for an applied magnetic field.

Neuromorphic computing using nonvolatile memories is expected to tackle the memory wall and energy efficiency bottleneck in the von Neumann system and to mitigate the stagnation of Moore’s law. However, an ideal artificial neuron possessing bio-inspired behaviors as exemplified by the requisite leaky-integrate-fire and self-reset (LIFT) functionalities within a single device is still lacking. Here, we report a new type of spiking neuron with LIFT characteristics by manipulating the magnetic domain wall motion in a synthetic antiferromagnetic (SAF) heterostructure. We validate the mechanism of Joule heating modulated competition between the Ruderman–Kittel–Kasuya–Yosida interaction and the built-in field in the SAF device, enabling it with a firing rate up to 17 MHz and energy consumption of 486 fJ/spike. A spiking neuron circuit is implemented with a latency of 170 ps and power consumption of 90.99 μW. Moreover, the winner-takes-all is executed with a current ratio >10 4 between activated and inhibited neurons. We further establish a two-layer spiking neural network based on the developed spintronic LIFT neurons. The architecture achieves 88.5% accuracy on the handwritten digit database benchmark. Our studies corroborate the circuit compatibility of the spintronic neurons and their great potential in the field of intelligent devices and neuromorphic computing. Designing bio-inspired artificial neurons within a single device is challenging. Here, the authors demonstrate a spintronic neuron with leaky-integrate-fire and self-reset characteristics and corroborate a new trajectory of all-spin neuromorphic computing hardware holistic implementation.

We report a breakthrough in the hardware implementation of energy-efficient all-spin synapse and neuron devices for highly scalable integrated neuromorphic circuits. Our work demonstrates the successful execution of all-spin synapse and activation function generator using domain wall-magnetic tunnel junctions. By harnessing the synergistic effects of spin-orbit torque and interfacial Dzyaloshinskii-Moriya interaction in selectively etched spin-orbit coupling layers, we achieve a programmable multi-state synaptic device with high reliability. Our first-principles calculations confirm that the reduced atomic distance between 5 d and 3 d atoms enhances Dzyaloshinskii-Moriya interaction, leading to stable domain wall pinning. Our experimental results, supported by visualizing energy landscapes and theoretical simulations, validate the proposed mechanism. Furthermore, we demonstrate a spin-neuron with a sigmoidal activation function, enabling high operation frequency up to 20 MHz and low energy consumption of 508 fJ/operation. A neuron circuit design with a compact sigmoidal cell area and low power consumption is also presented, along with corroborated experimental implementation. Our findings highlight the great potential of domain wall-magnetic tunnel junctions in the development of all-spin neuromorphic computing hardware, offering exciting possibilities for energy-efficient and scalable neural network architectures. The authors demonstrate all-spin synapses and neurons using domain wall-magnetic tunnel junctions, utilizing synergistic spin-orbit torque and Dzyaloshinskii-Moriya interaction. The intrinsic linearity is required for compact and energy-efficient bio-inspired hardware for neuromorphic computing.

Stretchable electronics that prevalently adopt chemically inert metals as sensing layers and interconnect wires have enabled high-fidelity signal acquisition for on-skin applications. However, the weak interfacial interaction between inert metals and elastomers limit the tolerance of the device to external friction interferences. Here, we report an interfacial diffusion-induced cohesion strategy that utilizes hydrophilic polyurethane to wet gold (Au) grains and render them wrapped by strong hydrogen bonding, resulting in a high interfacial binding strength of 1017.6 N/m. By further constructing a nanoscale rough configuration of the polyurethane (RPU), the binding strength of Au-RPU device increases to 1243.4 N/m, which is 100 and 4 times higher than that of conventional polydimethylsiloxane and styrene-ethylene-butylene-styrene-based devices, respectively. The stretchable Au-RPU device can remain good electrical conductivity after 1022 frictions at 130 kPa pressure, and reliably record high-fidelity electrophysiological signals. Furthermore, an anti-friction pressure sensor array is constructed based on Au-RPU interconnect wires, demonstrating a superior mechanical durability for concentrated large pressure acquisition. This chemical modification-free approach of interfacial strengthening for chemically inert metal-based stretchable electronics is promising for three-dimensional integration and on-chip interconnection. Stretchable electronics require high interfacial strength between the inert metal and elastomer components for durable interconnection applications. Cao et al. show a chemical modification-free interfacial diffusion-induced cohesion strategy, using hydrophilic polyurethane to induce hydrogen bonding of gold grains.

Sodium metal is a promising anode material for sodium metal batteries (SMBs) due to its high theoretical specific capacity and low electrochemical potential. However, its practical implementation is severely limited by dendrite formation, which causes short circuits and safety issues. Here, we introduce a separator modification strategy using Ag nanoparticles decorated with two-dimensional diamane on a commercial polypropylene (PP) substrate (Ag-diamane/PP) to enhance the performance of sodium metal anodes (SMAs). The synergistic effect between the sodiophilic Ag nanoparticles and the diamane network not only accelerates Na⁺ transport through the modified separator but also reduces interfacial resistance. This dendrite-suppression effect was systematically validated using in situ optical microscopy and ex situ scanning electron microscopy. Symmetric Na||Na cells incorporating the Ag-diamane/PP separator exhibit exceptional cycling stability, maintaining more than 3800 h of operation at 2 mA cm−2 with a capacity of 1 mAh cm−2. Furthermore, a full-cell configuration with a Na3V2(PO4)3@C cathode, Ag-diamane/PP separator, and Na metal anode delivers a high reversible capacity of 94.35 mAh g−1 and stable cycling for 270 cycles. This work highlights the Ag-diamane/PP separator as a promising solution for advancing dendrite-free SMBs with long-term cycling stability and high energy density.

The discovery of ferromagnetism in van der Waals (vdW) materials has enriched the understanding of two-dimensional (2D) magnetic orders and opened new avenues for fundamental physics research and next generation spintronics. However, achieving ferromagnetic order at room temperature, along with strong perpendicular magnetic anisotropy, remains a significant challenge. In this work, we report wafer-scale growth of vdW ferromagnet Fe 3 GaTe 2 using molecular beam epitaxy. The epitaxial Fe 3 GaTe 2 films exhibit robust ferromagnetism, exemplified by high Curie temperature ( T C  = 420 K) and large perpendicular magnetic anisotropy (PMA) constant K U  = 6.7 × 10 5  J/m 3 at 300 K for nine-unit-cell film. Notably, the ferromagnetic order is preserved even in the one-unit-cell film with T C reaching 345 K, benefiting from the strong PMA ( K U  = 1.8×10 5  J/m 3 at 300 K). In comparison to exfoliated Fe 3 GaTe 2 flakes, our epitaxial films with the same thickness show the significant enhancement of T C , which could be ascribed to the tensile strain effect from the substrate. The successful realization of wafer-scale ferromagnetic Fe 3 GaTe 2 films with T C far above room temperature represents a substantial advancement (in some aspects or some fields, e.g. material science), paving the way for the development of 2D magnet-based spintronic devices. While the list of van der Waals magnetic materials has expanded considerably over the last few years, these are still typically limited to low temperatures. Here, Wu et al report wafer scale growth, and robust room temperature ferromagnetism in Fe3GaTe2.

Progress in nanocrystal synthesis and self-assembly enables the formation of highly ordered superlattices. Recent studies focused on spherical particles with tunable attraction and polyhedral particles with anisotropic shape, and excluded volume repulsion, but the effects of shape on particle interaction are only starting to be exploited. Here we present a joint experimental–computational multiscale investigation of a class of highly faceted planar lanthanide fluoride nanocrystals (nanoplates, nanoplatelets). The nanoplates self-assemble into long-range ordered tilings at the liquid–air interface formed by a hexane wetting layer. Using Monte Carlo simulation, we demonstrate that their assembly can be understood from maximization of packing density only in a first approximation. Explaining the full phase behaviour requires an understanding of nanoplate-edge interactions, which originate from the atomic structure, as confirmed by density functional theory calculations. Despite the apparent simplicity in particle geometry, the combination of shape-induced entropic and edge-specific energetic effects directs the formation and stabilization of unconventional long-range ordered assemblies not attainable otherwise. Thin lanthanide fluoride nanoplates are shown to self-organize at the liquid/air interface into long-range-ordered two-dimensional planar tilings. In this joint experimental–computational, multiscale investigation, the assembly behaviour is shown to be dictated by entropic forces arising from particle shape and enthalpic forces arising from interaction anisotropy.

Thermally activated delayed fluorescence (TADF) materials, which can harvest all excitons without utilizing any noble metals to emit light, are becoming the key cornerstone for developing the next generation of organic light-emitting diode (OLED) devices. In recent years, TADF materials are attracting numerous attentions as a new surge of research focuses on both science and industry owing to their high efficiency, low power consumption, and low production cost attributes when applied to white OLEDs. The design and application of TADF in WOLED devices have also experienced the rapid development in fundamental science and industrial technology perspectives. In the present review, the specific reverse intersystem crossing mechanism and evolution of TADF is outlined firstly, and then the latest research progress of TADF-WOLEDs is summarized and discussed. TADF/conventional fluorescence, TADF/phosphorescence, all TADF and TADF exciplex-based WOLEDs are categorized and elaborated in terms of the device structure, working mechanism, efficiency, color-rendering index, etc. Finally, we conclude with the future challenges and opportunities in high-quality TADF devices and application area.

We report on the development of green and white OLEDs with high efficiency based on Bis(4-(9,9-dimethylacridin-10(9H)-yl) phenyl)methanone (DMAC-BP) manufactured by a facile vacuum evaporation technique via device interfaces engineering. Single, double, and three organic layer undoped OLEDs based on DMAC-BP have been fabricated. Among the developed green devices, the performance of three-layer structured OLEDs is the optimum when mCP (1,3-Bis(carbazol-9-yl)benzene) works as the hole transport layer (HTL) and electron block layer (EBL). The measured maximum external quantum efficiency (EQE), current efficiency (CE), power efficiency (PE), and luminance are 8.1%, 25.9 cd/A, 20.3 lm/W, and 42,230 cd/m 2 , respectively. Importantly, the OLEDs retain the most of their performance at 1000 cd/m 2 , and the EQE, CE, and PE are 7.2%, 23.7 cd/A, and 19.1 lm/W, respectively. The achieved high efficiency is attributed to the bipolar transport characteristics of DMAC-BP and the matched bandgap between HTL and emission layer (EML). In addition, WOLEDs with DMAC-BP as green layer are all warm white devices. Among them, the structure of green-red-blue (device W3) demonstrates the best performance with a maximum EQE and brightness of 4.4% and 7525 cd/m 2 . Our findings will facilitate the great potential applications of undoped TADF emitters, and establish a good foundation for the preparation of high-efficiency and low-cost commercial OLEDs.