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ABSTRACT Permanent magnets with strong anisotropy and high coercivity underpin modern information and energy technologies, yet rare‐earth‐free alternatives remain limited. Here, we show that thickness engineering via mechanical exfoliation induces hard magnetic behavior in the van der Waals ferromagnet Fe₃GaTe₂. Bulk crystals exhibit Curie temperatures above 350 K but negligible room‐temperature coercivity. When thinned below ∼100 nm, the coercive field is dramatically enhanced, reaching nearly 1 T at room temperature for in‐plane fields—comparable to conventional hard magnets. Micromagnetic analysis reveals a crossover in magnetization reversal from domain‐mediated processes in bulk samples to quasi‐coherent rotation in thin flakes, driven by increased effective anisotropy and suppressed domain formation. This thickness‐dependent transition enables tuning of magnetic hardness without chemical modification. Combined with high saturation magnetization and robust room‐temperature performance, Fe₃GaTe₂emerges as a promising rare‐earth‐free material for spintronic applications. Its layered structure further allows integration into van der Waals heterostructures, where large in‐plane coercivity can stabilize magnetic states against perturbations and interlayer coupling, offering potential for high‐density nonvolatile memory and domain‐wall‐based devices. 

Abstract Advancements in fabrication methods have shaped new computing device technologies. Among these methods, depositing electrical contacts to the channel material is fundamental to device characterization. Novel layered and 2D materials are promising for next‐generation computing electronic channel materials. Direct‐write printing of conductive inks is introduced as a surprisingly effective, significantly faster, and cleaner method to contact different classes of layered materials, including graphene (semi‐metal), MoS₂(semiconductor), Bi‐2212 (superconductor), and Fe₅GeTe₂(metallic ferromagnet). Based on the electrical response, the quality of the printed contacts is comparable to what is achievable with resist‐based lithography techniques. These devices are tested by sweeping gate voltage, temperature, and magnetic field to show that the materials remain pristine post‐processing. This work demonstrates that direct‐write printing is an agile method for prototyping and characterizing the electrical properties of novel layered materials. 

Hyperbolic phonon polaritons (HPPs) are coupled oscillations of anisotropic lattice vibrations and electromagnetic fields that confine the latter to the nanoscale, enabling novel nano‐polaritonic devices. While HPPs have been identified in multiple layered materials, achieving advanced control and manipulation—particularly polariton canalization for unidirectional energy flow—often necessitates complex device fabrications or crystal modifications. Here we visualize and elucidate the properties of in‐plane hyperbolicity in α‐V₂O₅, a layered compound with a highly anisotropic permittivity tensor. We show unidirectional Poynting‐vector propagation of polaritons in α‐V₂O₅without additional treatments. Combined with theoretical modeling, our infrared nano‐imaging studies unveil a novel form of polariton canalization, with its dispersion contour continuously tunable by the incident light frequency. Additionally, we provide a theoretically calculated permittivity phase diagram for tailoring polaritonic wavefronts. These findings suggest that the metal‐oxide α‐V₂O₅holds great promise for on‐demand light canalization and control at the nanoscale. 

van der Waals magnetic materials open up exciting possibilities to investigate fundamental spin properties in low-dimensional systems and to build compact functional spintronic structures. This review focuses on the recent progress in two-dimensional(2D) magnets that explore beyond the homogenous magnetically-ordered state, including magnons (spin waves), magnetic skyrmions, and complex magnetic domains. Properties of these spin and topology excitations in 2D magnets provide insights into spin-orbit interactions and other forms of coupling between electrons, phonons, and spin-dependent excitations. Such spin-based quasiparticles can also serve as information carriers for next-generation high-speed computing elements. We will first lay out the general theoretical basis of dynamical responses in magnetic systems, followed by detailed descriptions of experimental progress in magnons and spin textures (including magnetic domains and skyrmions). Discussion on the experimental techniques and future perspectives are also included. 

The advent of layered materials has unveiled new opportunities for tailoring electromagnetic waves at the subwavelength scale, particularly through the study of polaritons, a hybrid light–matter excitation. In this context, twist-optics, which investigates the optical properties of twisted stacks of van der Waals (vdW) layered specimens, has emerged as a powerful tool. Here, we explore the tunability of phonon polaritons in α-V₂O₅via interlayer twisting using scanning nano-infrared (IR) imaging. We show that the polaritonic response can be finely adjusted by varying their interlayer electromagnetic coupling, allowing for precise control over the propagation direction and phase transition from open unidirectional iso-frequency contours to closed elliptic geometries. Our experimental results, in conjugate with theoretical modeling, reveal the mechanisms underpinning this tunability, highlighting the role of twist-induced nano-light modifications for advanced nanophotonic control at the nanoscale.