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Optical gain materials activated by dopants are playing pivotal roles in fiber amplifiers, solid-state lasers and biological imaging. Achieving high photoluminescence (PL) efficiency in a stable matrix by regulating the chemical surroundings of dopants in an inert glass matrix remains a challenge. Here, we report a novel method for regulating the chemical surroundings of dopants by modulating the network structure of the glass matrix, achieving regulation of dopant PL efficiency. The luminescent properties of glass were adjusted not only by altering its composition, but also more importantly by controlled nanocrystallization. Furthermore, by utilizing lattice-site substitution engineering, the spectral shape and PL efficiency of active centers can be regulated by controlling the method of cation substitution at sub-nanometer scale. [ABSTRACT FROM AUTHOR]

This state-of-the-art overview highlights the significance of high performance shape memory polymer/nanodiamond nanocomposites. Nanodiamond reinforced polymeric nanocomposites have been designed and advantageously studied for the design, microstructure, physical properties, structure–property relation/phenomenon, shape memory effects, and possible technical advancements. Nanodiamond filled polymer matrices studied for shape memory effects include polyesters, polyurethane, poly(N-isopropylacrylamide), epoxy, polyaniline, chitosan, etc. Addition of nanodiamond especially functional nanoparticles may develop physical and/or covalent interactions with matrices to form interlinking/cross-linking network responsible for active shape fixing/recovery behavior. Noteworthy thermo-responsive, electroactive, photoactive, photothermal, and magnetic sensitive shape memory effects have been observed. Application areas of shape memory polymer/nanodiamond nanocomposites observed so far are smart strain sensing and wearable electronics, antibacterial and biosensing, and civil and engineering related areas. [ABSTRACT FROM AUTHOR]

Currently, most of the finger rehabilitation mechanisms achieve the desired motion by scale synthesis or using multi-degree-of-freedom (DOF) mechanisms, which cannot simultaneously achieve the requirements of posture and trajectory for finger rehabilitation. Aiming to solve this problem, this study proposes a single-DOF noncircular pulley-five-bar finger rehabilitation mechanism, obtains the pose requirements of finger movement and extracts four important poses. The solution domain of the five-bar mechanism with four poses was solved using the solution-region synthesis method, and the noncircular pulley was used to constrain two rods, making it a single-DOF mechanism. According to the requirements of the finger rehabilitation mechanism and considering the force transmission characteristics of the mechanism, the mechanism parameter optimization model is established, and the optimal parameters are optimized. The calculation model of noncircular pulley transmission is established, and the profile of noncircular pulley is solved according to the obtained rod rotation angle relationship. A finger rehabilitation device was developed, and an experimental study was performed. It was found that the device passed four poses, and the actual trajectory was consistent with the target trajectory. It is confirmed that the single-DOF noncircular pulley-five-bar finger rehabilitation mechanism proposed is effective, and solution method are correct. [ABSTRACT FROM AUTHOR]

Epitaxy, a process to prepare crystalline materials in nanostructures and thin films, is the core technology for preparing high-quality materials as a key enabler of next-generation microelectronics and quantum information system. Progress in epitaxy has been expanding the choice of materials and their heterostructures beyond the combinations limited by materials compatibility. However, the improvement of material quality, physical implementation of materials with unique properties, and integration of incommensurate materials in an architecture have been the challenging issues. Emerging materials, including 2D materials and quantum materials, have opened opportunities to study epitaxy mechanisms and realize various functional devices. Acceleration of discovery and progress in epitaxy research should be accomplished by "understanding of epitaxy under various circumstances at multiple length scales" and "integration of experiments and models." In the perspective, a basic summary of the status of epitaxially grown materials, the challenges in epitaxy research, and integration of modeling epitaxy and ultimate control of the epitaxy process with advanced characterization techniques are discussed., (© 2025 The Author(s). Small Methods published by Wiley‐VCH GmbH.)

2D van der Waals (vdW) magnets, which extend to the monolayer (ML) limit, are rapidly gaining prominence in logic applications for low-power electronics. To improve the performance of spintronic devices, such as vdW magnetic tunnel junctions, a large effective spin polarization of valence electrons is highly desired. Despite its considerable significance, direct probe of spin polarization in these 2D magnets has not been extensively explored. Here, using 2D vdW ferromagnet of CrTe 2 as a prototype, the spin degrees of freedom in the thin films are directly probed using Mott polarimetry. The electronic band of 50 ML CrTe 2 thin film, spanning the Brillouin zone, exhibits pronounced spin-splitting with polarization peaking at 7.9% along the out-of-plane direction. Surprisingly, atomic-layer-dependent spin-resolved measurements show a significantly enhanced spin polarization in a 3 ML CrTe 2 film, achieving 23.4% polarization even in the absence of an external magnetic field. The demonstrated correlation between spin polarization and film thickness highlights the pivotal influence of perpendicular magnetic anisotropy, interlayer interactions, and itinerant behavior on these properties, as corroborated by theoretical analysis. This groundbreaking experimental verification of intrinsic effective spin polarization in CrTe 2 ultrathin films marks a significant advance in establishing 2D ferromagnetic atomic layers as a promising platform for innovative vdW-based spintronic devices., (© 2024 Wiley‐VCH GmbH.)