Size-dependent anisotropy in lattice parameters governs the bright-exciton fine-structure splitting (BEFSS) in CsPbI3 nanocrystals. By using the continuum elastic theory, we demonstrate that an additional lattice anisotropy in a pseudocubic nanocrystal is determined by the elastic coupling between bulk and surfaces. For the CsPbI3 nanocrystal in orthorhombic phase, it reveals that the surface stress anisotropy of the (001) surface plays a more important role than that of the (110) surface in inducing the size-dependent lattice anisotropy. According to the first-principles calculations, the intrinsic surface stress anisotropy is relatively small for either (110) or (001) surface. As organic ligands are always involved in the synthesis of CsPbI3 nanocrystals, they may introduce stochastic surface stress anisotropy and thus result in divergency of BEFSS. Therefore, we further study the surface with typical substitutional short-chain ligands, namely methylammonium and formate ions. It turns out that the surface stress anisotropy is large on the (110) surface but small on the (001) surface due to the cooperative geometric effect of ligand and surface structure. Consequently, the BEFSS variations become negligible at various coverages with the short-chain ligands. These findings enable precise control of the BEFSS through surface stress engineering by carefully selecting the suitable ligands, improving the application of CsPbI3 nanocrystals in quantum optics and information technologies.

This letter reports high-performance VCMA-MRAM devices fabricated on 12-inch wafer. By leveraging a bottom-pinned MTJ stack and synthetic antiferromagnet engineering, the optimized structure reduces stray field to 1.5 mT, enabling highly symmetric switching with a VCMA coefficient of 71.2 fJ/V & centerdot;m. Meanwhile, a thicker MgO barrier enhances device robustness and endurance exceeding 1014 cycles. Moreover, the devices sustain fast voltage-driven switching down to 0.6 ns while maintaining a low write energy of 30 fJ/bit, surpassing prior state-of-the-art MRAM counterparts. Our results establish bottom-pinned VCMA-MRAM as a promising candidate for ultra-fast, energy-efficient, and high-endurance embedded nonvolatile memory.

Magnonic spin current generation in antiferromagnets has emerged as an important topic in spintronics, where a strong external magnetic field or a Dzyaloshinskii-Moriya interaction (DMI) is generally required. Recently, a type of antiferromagnets characterized by momentum-dependent nonrelativistic spin splitting bands, referred to as altermagnets, has offered an unprecedented approach to generating magnon spin current without the constraints of a magnetic field or DMI. Here, we demonstrate the magnon spin splitting Nernst effect (MSSNE) in the LuFeO_{3} films, where applying a longitudinal temperature gradient generates a transverse magnonic spin current. Four critical types of evidence support the observed MSSNE originating from the spin splitting of magnon bands, as further corroborated by the symmetry analysis, rather than the DMI. Our findings not only demonstrate the MSSNE but also highlight the intriguing magnonic properties in the altermagnets, which have emerged as a promising material platform for antiferromagnetic spintronic applications.

We introduce a methodology for investigating vortex solitons (VSs) within quasi-phase-matched (QPM) photonic crystals, featuring competing quadratic and cubic nonlinearities. The photonic crystal is introduced with a checkerboard structure, which is feasible through contemporary technological advancements. The VS family is constructed as quadrupole and 8-pole configurations, with the quadrupole solitons displaying rhombus and square modes depending on different phase-matching conditions. Notably, an intriguing transformation from the quadrupole to the 8-pole configuration can be achieved by modulating the cubic nonlinear coefficient. Additionally, the square-shaped VSs would transfer to rhombus patterns by adjusting the power and size of the checkerboard cell in the framework of cubic nonlinearity. This work presents a versatile and powerful tool for exploring and manipulating vortex solitons in QPM photonic structures, with potential applications in optical signal processing, optical communications, and nonlinear optics research.

Regulating magnetism of a metal-organic framework (MOF) is highly desirable in magnetoelectric devices. Single-crystalline MOFs of [(CH3)2NH2]2[FeIIIFe2-xIICoxII(HCOO)9] (x = 0, 0.2, 0.3, 0.6) with an unprecedented (412·63)1(49·66)2 topology were synthesized. These MOFs exhibit distinct antiferromagnetism, and the Néel temperature (TN) changes from 32.8 to 29.0 K with increasing x. After field cooling from above TN to 2 K, these MOFs demonstrate giant exchange bias (EB) featured by a significant vertical and simultaneous horizontal shift in an almost linear curve of magnetization (M) versus the field (H). As the temperature rises, the M-H curve becomes hysteretic, with significantly increased coercivity and a diminished EB field. In combination with the Monte Carlo simulations, this EB effect is attributed to a large enough (negligible) anisotropy of FeII (FeIII) ions and antiferromagnetic exchange coupling between FeII and FeIII ions. This work provides a clue to designing a linear magnetic field sensor by using MOFs.

Extrinsic scattering by impurities can alter the directions of flow and spin polarization of electrons, significantly advancing the generation and manipulation of electronic spin currents. It should also enable control of these properties of magnons, realizing the generation and manipulation of magnonic spin currents. However, no experimental observation of extrinsic scattering induced analogous magnon phenomenon has been made so far. Here, we report the observation of a thermal voltage converted from the extrinsic scattering induced magnon spin swapping effect in a ferrimagnetic insulator Bi-doped yttrium iron garnet Bi1Y2Fe5O12, triggered by an in-plane temperature gradient. The thermal voltage disappears without Bi dopants and shows nearly linear scaling with the Bi amount, leading to an unambiguous ascription of this magnon transport phenomenon to the extrinsic scattering by impurities and ruling out other possible thermoelectric mechanisms. Our study not only provides compelling evidence for the extrinsic scattering induced magnon spin swapping effect by Bi impurities doping, but it also expands the range of materials and the means for controlling magnon transport.

We introduce a technique for generating vortex solitons (VSs) in a Rydberg-dressed triangular optical lattice. A family of VSs is observed, constructed as ring-shaped, three-core, and six-core vortex modes. The topological charges of VSs supported in this system are m = +/- 1, +/- 2. Notably, the triangular lattice potential and Rydberginduced nonlocal nonlinearities exert a prominent influence on the generation and stability domains of these VSs. The space distribution of VSs can be modulated by the direction of incident light. Further studies show that the ring-shaped VSs are more stable than six-core VSs.

The discovery of two-dimensional magnetic materials has provided an ideal platform for exploring physical phenomena in the two-dimensional limit. However, intrinsic two-dimensional antiferromagnetic materials have been rarely reported, limiting systematic studies of their electronic properties. The discovery of novel intrinsic two-dimensional antiferromagnets and the development of robust synthesis strategies, therefore, remain significant challenges. Here, we report the chemical vapor deposition synthesis of CrOCl monolayer films and nanosheets that exhibit excellent air stability. The CrOCl morphology is tunable, ranging from two-dimensional nanosheets to three-dimensional flower-like structures, with lateral sizes ranging from several microns to continuous monolayer films. Structural characterization confirms the material’s composition and high crystalline quality. Furthermore, magnetic measurements, supported by theoretical calculations, reveal a Néel temperature for CrOCl of ≈ 14 K. This work provides a reliable route for preparing two-dimensional antiferromagnetic materials. The development of novel two-dimensional antiferromagnets is crucial for enhancing the performance of spintronic devices. Here, authors realize the synthesis of CrOCl monolayer films and nanosheets that exhibit excellent performance.

Ternary copper halides with an eco-friendly property have emerged as attractive candidates to replace toxic lead-containing perovskites for light-emitting diodes (LEDs), yet achieving long-wavelength electroluminescence remains unexplored. Herein, we report the first realization of orange-emitting LEDs (595 nm) based on nontoxic organic-inorganic PEA4Cu4I4 (PEA = β-phenylethylamine) films enabled by a nonionic surfactant poly(propylene glycol) bis(2-aminopropyl ether) (APPG) chemisorption. Experimental and theoretical analyses rationalize that the APPG additive has strong chemisorption with the Cu-I framework within the grain boundaries of PEA4Cu4I4 films, which not only improves the film's morphology but also passivates the iodine vacancy defects. Moreover, the APPG additive can raise the ionization energy and increase the carrier mobility of PEA4Cu4I4 films, thereby balancing the charge transport. Consequently, we achieve orange LEDs made from APPG-treated PEA4Cu4I4 films, showing an external quantum efficiency of 1.21%, and the operational stability of the treated device is greatly prolonged, resulting from the suppressed iodine ion migration.

During deep hole machining, the significant overhang of the boring bar leads to a drastic decrease in stiffness, resulting in severe vibration issues. This causes serious machining noise, reduced material removal rates, decreased tool life, and poor surface quality of the workpiece. In order to improve the vibration resistance of the boring bar, this paper proposes a vibration-damping boring bar with a particle damping vibration absorber. Firstly, a dynamic model of the boring bar was established, and its modal characteristics were analyzed using the finite element method (FEM). The discrete element method (DEM) was then employed to develop a contact model for the damping particles, clarifying the energy dissipation mechanism. The influence of the absorber's structural design and damping particle parameters on energy dissipation characteristics were further analyzed using EDEM simulation software. Finally, modal testing and cutting experiments were conducted to measure the modal parameters and vibration signals of the boring bar with different particles. Comparative evaluations were made against a carbide boring bar, providing a holistic assessment of the effectiveness and applicability of particle damping. The experimental results indicate that using YG6 tungsten carbide particles with a diameter of 0.5 mm and a filling rate of 90

Physics-inspired computing paradigms, such as Ising machines, are emerging as promising hardware alternatives to traditional von Neumann architectures for tackling computationally intensive combinatorial optimization problems (COPs). While quantum, optical, and electronic devices have garnered significant attention for their potential in realizing Ising machines, their translation into practical systems for industry-relevant applications remains challenging, with each approach facing specific limitations in power consumption and speed. To address this challenge, we report the first chip-level spintronic Ising machine using voltage-controlled magnetoresistive random access memory. The core of our design leverages magnetic tunnel junctions (MTJs) driven by the voltage-controlled magnetic anisotropy effect to realize the probabilistic update of Ising spins through a new mechanism. It enables a latency below 1 ns and an energy consumption under 40 fJ per spin update, achieving a 1000-times improvement over previous current-driven MTJ-based implementations. We map two real-world COPs in electronic design automation-global routing and layer assignment-onto the Ising model and demonstrate high-quality results with an energy efficiency of 25000 solutions per second per watt. This outperforms state-of-the-art quantum and graphics processing units by six and seven orders of magnitude, respectively. These results establish voltage-controlled spintronics as a compelling route towards next-generation physics-inspired machine intelligence, offering a paradigm for ultra-low-power, high-speed, and scalable computation.

We demonstrate a terahertz (THz) emitter based on Pt/BiFeO3 heterostructures, leveraging the ultrafast strain-wave-driven spin dynamics for coherent THz generation. Femtosecond laser pulses absorbed in the Pt layer generate elastic strain waves that propagate into the epitaxial BiFeO3 thin films, deflecting the antiferromagnetic Néel vector and exciting out-of-plane spin-wave (magnons) via magnetostriction. These spin waves are converted into ultrafast charge currents through the inverse spin Hall effect in Pt, and then the charge currents excite significant THz radiations. The excitation mechanism, confirmed by polarization-independent emission and a cosine azimuthal dependence, excludes optical nonlinearities and highlights the importance of the interface strain. While electric-field control of THz emission was not experimentally realized, this work establishes Pt/BiFeO3 as a promising platform for nonvolatile, electrically tunable spintronic THz emitters, exploiting the inherent magnetoelectric coupling of multiferroic BiFeO3.

Construction of a built-in electric field has been identified as an attractive improvement strategy for photoelectrochemical (PEC) water splitting by facilitating the carrier extraction from the inside to the surface. However, the promotion effect of the electric field is still restrained by the confined built-in area. Herein, we construct a microscale built-in electric field via gradient oxygen doping. The octahedral configuration of the synthesized CdIn2S4 (CIS) provides a structural basis, which enables the subsequent oxygen doping to reach a depth of similar to 100 nm. Accordingly, the oxygen-doped CIS (OCIS) photoanode exhibits a microscale built-in electric field with band bending. Excellent PEC catalytic activity with a photocurrent density of 3.69 mA cm(-2) at 1.23 V vs. RHE is achieved by OCIS, which is 3.1 times higher than that of CIS. Combining the results of thorough characterization and theoretical calculations, accelerating migration and separation of charge carriers have been determined as the reasons for the improvement. Meanwhile, the recombination risk at the doping centers has also been reduced to the minimum via optimal experiments. This work provides a new-generation idea for constructing a built-in electric field from the view point of bulky configuration towards PEC water splitting.

The rare-earth Eu-based compounds with a unique half-filled 4f orbital have attracted an amount of research interest recently. Here, we synthesized EuTe(001) single-crystal thin films on SrTiO3(001) substrate via molecular beam epitaxy (MBE). The scanning tunneling microscopy and x-ray diffraction results indicate that the grown EuTe thin films orientated as EuTe[100]//SrTiO3[110] in plane. In the angle-resolved photoemission spectroscopic (ARPES) measurements, the grown EuTe films show a semiconductive band structure with the valence band maximum lying on the center point of the Brillouin zone. The bandgap size of EuTe was further identified by the optical transmission spectra as 2.2 eV. The antiferromagnetic transition temperature of the grown EuTe film is 10.5 K measured by a superconductive quantum interference device (SQUID). Our results provide important information on the fundamental electronic structures for the further research and applications of the Eu-based compounds.

We report the picosecond spin current generation from the interface between a heavy metal and a vicinal antiferromagnet insulator Cr2O3 by laser pulses at room temperature and zero magnetic field. It is converted into a detectable terahertz emission in the heavy metal via the inverse spin Hall effect. The vicinal interfaces are apparently the source of the picosecond spin current, as evidenced by the proportional terahertz signals to the vicinal angle. We attribute the origin of the spin current to the transient magnetic moment generated by an interfacial nonlinear magnetic-dipole difference-frequency generation. We propose a model based on the in-plane inversion symmetry breaking to quantitatively explain the terahertz intensity with respect to the angles of the laser polarization and the film azimuth. Our work opens new opportunities in antiferromagnetic and ultrafast spintronics by considering symmetry breaking.

The edge of two-dimensional (2D) flakes of transition metal dichalcogenide (TMD) profoundly influences their optical, electronic, catalytic, and magnetic properties due to the asymmetric atomic configurations on the edge. As a reverse process of growth, the etching of monolayer MoS2 flakes can be modulated by tuning the sulfur stoichiometric ratio in chemical vapor deposition. Here, we report studies of the high-density formation of etched pores with defined orientations on MoS2 flakes. Structural analysis reveals that these pores are bound by zigzag edges. Our measurements show that the saturation magnetization of etched MoS2 flakes can be up to five times higher than that of unetched counterparts, indicating that increased zigzag edge density enhances the ferromagnetism of MoS2 flakes. These observations provide valuable insights for tailoring the edge density of 2D TMD flakes to optimize properties for targeted applications.

Since antiferromagnets (AFMs) have the potential to drive spintronic devices to higher speed and stability, generation, and transportation of terahertz (THz) spin currents in AFM/heavy metal (HM) structures have been extensively studied. However, effective methods to optimize the efficiency of THz spin current transmission at the interface are still lacking. Here, we demonstrated a significant enhancement of THz spin current in NiO/Pt structures by using THz emission spectroscopy. The spin transmittance is increased by up to a factor of 3.7 after heating the samples at a temperature of 350 degrees C for 0.5 h. This enhancement can be attributed to the optimization of the NiO/Pt interface resulting from the heating process. In contrast, the control samples NiO/Cu/Pt and NiO did not exhibit a similar enhancement, indicating that the improvement in spin current transmission is specific to the NiO/Pt interface. The scanning transmission electron microscopy is used to observe the optimized interface and confirmed the reason for THz signal enhancement. Our work paves a way for the modulation of AFM/HM interfaces and the optimization of ultrafast spintronic devices based on AFMs.

Polarization-sensitive solar-blind ultraviolet (UV) photodetectors are essential in both civilian and military applications. 1D perovskites derivative Rb2CuCl3 holds promise for polarization-sensitive solar-blind UV photodetectors due to its wide direct bandgap, anisotropic crystal structure, and long carrier lifetime. However, no studies on the polarization properties of Rb2CuCl3 are reported. Here, the electronic structural anisotropy of Rb2CuCl3 is confirmed by calculating the partial charge density distribution in the ac-plane and bc-plane. Then, the Raman-active modes and corresponding atomic vibration modes are explored within the bc-plane through joint experimental and theoretical Raman spectroscopy. Besides, angle-resolved Raman, photoluminescence, and absorption spectroscopy reveal the intriguing anisotropic photoelectric characteristics of Rb2CuCl3 microwires (MWs). By using single Rb2CuCl3 MW as the photoactive layer, a polarization-sensitive solar-blind UV photodetector is fabricated, showing high photoresponsivity of 78 mA W-1 and photocurrent anisotropy ratio of approximate to 1.7 at 265 nm. Importantly, the proposed photodetectors without encapsulation exhibit excellent stability in ambient air, retaining the original photocurrent after two months, showcasing practical applicability. This study underscores the promise of Rb2CuCl3 for high-performance polarization-sensitive solar-blind UV photodetectors, contributing valuable insights into its electronic structure, photoelectric properties, and practical applicability.

Taking into account the influence of process, voltage, temperature (PVT) and environmental variations on the entropy of random bits generated by the VC-MTJ, this work proposes a lightweight post-processing technique named AXprime, which leverages the avalanche effect of non-cryptographic hash functions to effectively mitigate biases and bit correlations in the raw VC-MTJ bit streams. In comparison to recent work based on Add operations or substitution box, our AXprime approach demonstrates its effectiveness in handling raw data with biases of up to 39% and with strong correlations. Furthermore, compared to extensively commercially-used post-processing methods such as Linear Feedback Shift Register (LFSR) and Advanced Encryption Standard (AES), the implementation of AXprime-based post-processing hardware not only meets all NIST 800-22 test standards, but also improves the Figure of Merit (FoM) value by 1.7x and 18.8x respectively, achieving a good trade-off between performance and power consumption.