The emergence of intrinsic two-dimensional (2D) magnetic materials has spurred exploration of exotic physical phenomena at the atomic limit, while also opening new avenues for the design of compact, ultra-low-power spintronic devices. In contrast to the widely studied layered magnets, the ternary nonlayered magnets with excellent stability remain relatively unexplored. A key challenge lies in the scalable fabrication of high-quality, large-area samples. Herein, we propose a dual-confined chemical vapor deposition strategy for the first-time synthesis of 2D nonlayered ferrimagnetic FeCr₂Te₄ nanosheets. The as-grown nanosheets exhibit lateral dimensions up to 400 μm and outstanding stability under high-temperature and harsh chemical conditions. The Curie temperature of the samples is independent of thickness. Notably, a temperature-tunable antiferromagnetic state emerges in thicker nanosheets, driven by weak interlayer exchange coupling. Furthermore, the nanosheets exhibit an extrinsic skew-scattering-dominated anomalous Hall effect, with a high carrier concentration of 10²⁰ cm⁻³ and mobility exceeding 30 cm²·V⁻¹·s⁻¹. This work opens up new avenues for the synthesis of ternary nonlayered 2D magnetic materials and significantly expands the material platform for developing high-performance spintronic devices.

Ferroelectric-based optoelectronic devices can integrate light sensing, data storage, and in-memory computing, providing a compact and energy-efficient paradigm for artificial vision hardware. Here, we demonstrate an image reconstruction application based on vision associative memory in the single ferroelectric semiconductor α-In₂Se₃, enabling direct hardware-level emulation of advanced neuromorphic functionality without external computation or peripheral circuitry. This device utilizes light-induced nonvolatile ferroelectric polarization switching to tune interfacial band bending and carrier injection, thereby generating multilevel resistance states that function as synaptic weights and enable synaptic-like weight updates. Notably, its intrinsic ferroelectric polarization relaxation effect naturally mimics biological adaptive forgetting process. Several key visual synapse functions have been realized in the α-In₂Se₃ device, including the transition from short-term memory to long-term memory, paired-pulse facilitation, learning-forgetting-relearning behavior, long-term potentiation, long-term depression and Pavlov's classical conditioning. Importantly, we demonstrate a new image reconstruction strategy based on the memory decay curves of light-sensing images. By associating and comparing memory fragments of reference images, the original information can be restored. This work establishes a compact neuromorphic-vision platform that co-integrates photodetection, synaptic plasticity, nonvolatile memory, and image reconstruction based on associative memory within a single ferroelectric device. The resulting architecture provides a practical route toward energy-efficient artificial retinas and brain-inspired visual systems.

Two-dimensional (2D) semiconductors with intrinsic ferromagnetism are highly desirable for potential applications in next-generation spintronic and optoelectronic devices. However, controllable synthesis of intrinsic 2D magnetic semiconductor on a substrate is still a challenging task. Herein, large-area 2D non-layered rock salt (α-phase) MnSe nanosheets were grown on mica substrates, with the thickness changing from 54.2 to 0.9 nm (one unit cell), by chemical vapour deposition. The X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy measurements confirmed that the resulting 2D α-MnSe nanosheets were obtained as high-quality single crystals. The magnetic hysteresis loops and synchrotron X-ray measurements directly indicated the anomalous magnetic properties in α-MnSe nanosheets. Comprehensive analysis of the reasons for magnetic property revealed that the low-temperature phase transition, small number of stacking differences in crystals, and surface weak oxidation in (111)-oriented α-MnSe were the main mechanisms. Furthermore, α-MnSe nanosheets exhibited broadband photoresponse from 457 to 671 nm with an outstanding detectivity and responsivity behaviours. This study presents the detailed growth process of ultrathin 2D magnetic semiconductor α-MnSe, and its outstanding magnetic properties and broadband photodetection, which provide an excellent platform for magneto–optical and magneto–optoelectronic research.

Two-dimensional (2D) van der Waals (vdW) magnetic materials with reduced dimensionality often exhibit unexpected properties compared to their bulk counterparts. In particular, the mechanical flexibility of 2D structure, enhanced ferromagnetism at reduced layer thickness, as well as robust perpendicular magnetic anisotropy are quite appealing for constructing novel spintronic devices. The vdW vanadium diselenide (VSe₂) is an attractive material whose bulk is paramagnetic while monolayer is ferromagnetic with a Curie temperature (T_c) above room temperature. To explore its possible device applications, a detailed investigation on the thickness-dependent magnetism and strain modulation behavior of VSe₂ is highly demanded. In this article, the VSe₂ nanoflakes were controllably prepared via chemical vapor deposition (CVD) method. The few-layer single VSe₂ nanoflakes were found to exhibit magnetic domain structures at room temperature. Ambient magnetic force microscopy (MFM) phase images reveal a clear thickness-dependent magnetism and the MFM phase contrast is traceable for the nanoflakes of layer thickness below ~ 6 nm. Moreover, applying strain is found efficient in modulating the magnetic moment and coercive field of 2D VSe₂ at room temperature. These results are helpful for understanding the ferromagnetism of high temperature 2D magnets and for constructing novel straintronic devices or flexible spintronic devices.