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1. High-pressure induced Weyl semimetal phase in 2D Tellurium

   https://doi.org/10.1038/s42005-023-01460-1  

   Niu, Chang; Zhang, Zhuocheng; Graf, David; Lee, Seungjun; Wang, Mingyi; Wu, Wenzhuo; Low, Tony; Ye, Peide D. (December 2023, Communications Physics)

   Abstract Relativistic Weyl fermion quasiparticles in Weyl semimetal bring the electron’s chirality degree of freedom into the electrical transport and give rise to exotic phenomena. A topological phase transition from a topological trivial phase to a topological non-trivial phase offers a route to control electronic devices through its topological properties. Here, we report the Weyl semimetal phase in hydrothermally grown two-dimensional Tellurium (2D Te) induced by high hydrostatic pressure (up to 2.47 GPa). The unique chiral crystal structure gives rise to chiral fermions with different topological chiral charges ($${{C}}=-{{1}},+{{1}},{{and}}-{{2}}$$ $C=-1,+1,and-2$). The highly tunable chemical potential in 2D Te provides comprehensive information for understanding the pressure-dependent electron band structure. The pressure-induced insulator-to-metal transition, two-carrier transport, and the non-trivial π Berry phase shift in quantum oscillations are observed in the 2D Te Weyl semimetal phase. Our work demonstrates the pressure-induced bandgap closing in the inversion asymmetric narrow bandgap semiconductor 2D Te. 

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2. Ultrafast Laser Shock Straining in Chiral Chain 2D Materials: Mold Topology-Controlled Anisotropic Deformation

   https://doi.org/10.1007/s40820-025-01925-8  

   Liu, Xingtao; de_Camargo_Branco, Danilo; An, Licong; Wang, Mingyi; Jiang, Haoqing; Wang, Ruoxing; Wu, Wenzhuo; Cheng, Gary J (November 2025, Nano-Micro Letters)

   Abstract Tellurene, a chiral chain semiconductor with a narrow bandgap and exceptional strain sensitivity, emerges as a pivotal material for tailoring electronic and optoelectronic properties via strain engineering. This study elucidates the fundamental mechanisms of ultrafast laser shock imprinting (LSI) in two-dimensional tellurium (Te), establishing a direct relationship between strain field orientation, mold topology, and anisotropic structural evolution. This is the first demonstration of ultrafast LSI on chiral chain Te unveiling orientation-sensitive dislocation networks. By applying controlled strain fields parallel or transverse to Te’s helical chains, we uncover two distinct deformation regimes. Strain aligned parallel to the chain’s direction induces gliding and rotation governed by weak interchain interactions, preserving covalent intrachain bonds and vibrational modes. In contrast, transverse strain drives shear-mediated multimodal deformations—tensile stretching, compression, and bending—resulting in significant lattice distortions and electronic property modulation. We discovered the critical role of mold topology on deformation: sharp-edged gratings generate localized shear forces surpassing those from homogeneous strain fields via smooth CD molds, triggering dislocation tangle formation, lattice reorientation, and inhomogeneous plastic deformation. Asymmetrical strain configurations enable localized structural transformations while retaining single-crystal integrity in adjacent regions—a balance essential for functional device integration. These insights position LSI as a precision tool for nanoscale strain engineering, capable of sculpting 2D material morphologies without compromising crystallinity. By bridging ultrafast mechanics with chiral chain material science, this work advances the design of strain-tunable devices for next-generation electronics and optoelectronics, while establishing a universal framework for manipulating anisotropic 2D systems under extreme strain rates. This work discovered crystallographic orientation-dependent deformation mechanisms in 2D Te, linking parallel strain to chain gliding and transverse strain to shear-driven multimodal distortion. It demonstrates mold geometry as a critical lever for strain localization and dislocation dynamics, with sharp-edged gratings enabling unprecedented control over lattice reorientation. Crucially, the identification of strain field conditions that reconcile severe plastic deformation with single-crystal retention offers a pathway to functional nanostructure fabrication, redefining LSI’s potential in ultrafast strain engineering of chiral chain materials. 

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3. A review of the growth, doping, and applications of Beta-Ga2O3 thin films

   https://doi.org/10.1117/12.2302471  

   Teherani, Ferechteh H.; Khodaparast, Giti A.; Xu, Yaobin V.; Wu, Jinsong; Dravid, Vinayak P.; Pavlidis, Dimitris; Razeghi, Manijeh; McClintock, Ryan; Rogers, David J.; Park, Ji-Hyeon; et al (March 2018, Proc. SPIE 10533, Oxide-based Materials and Devices IX)

   β-Ga2O3 is emerging as an interesting wide band gap semiconductor for solar blind photo detectors (SBPD) and high power field effect transistors (FET) because of its outstanding material properties including an extremely wide bandgap (Eg ~4.9eV) and a high breakdown field (8 MV/cm). This review summarizes recent trends and progress in the growth/doping of β-Ga2O3 thin films and then offers an overview of the state-of-the-art in SBPD and FET devices. The present challenges for β-Ga2O3 devices to penetrate the market in real-world applications are also considered, along with paths for future work. 

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4. Recent Advances in Low‐Dimensional Nanomaterials for Photodetectors

   https://doi.org/10.1002/smtd.202300246  

   Kim, Jaehyun; Lee, Junho; Lee, Jong‐Min; Facchetti, Antonio; Marks, Tobin J.; Park, Sung Kyu (May 2023, Small Methods)

   Abstract New emerging low‐dimensional such as 0D, 1D, and 2D nanomaterials have attracted tremendous research interests in various fields of state‐of‐the‐art electronics, optoelectronics, and photonic applications due to their unique structural features and associated electronic, mechanical, and optical properties as well as high‐throughput fabrication for large‐area and low‐cost production and integration. Particularly, photodetectors which transform light to electrical signals are one of the key components in modern optical communication and developed imaging technologies for whole application spectrum in the daily lives, including X‐rays and ultraviolet biomedical imaging, visible light camera, and infrared night vision and spectroscopy. Today, diverse photodetector technologies are growing in terms of functionality and performance beyond the conventional silicon semiconductor, and low‐dimensional nanomaterials have been demonstrated as promising potential platforms. In this review, the current states of progress on the development of these nanomaterials and their applications in the field of photodetectors are summarized. From the elemental combination for material design and lattice structure to the essential investigations of hybrid device architectures, various devices and recent developments including wearable photodetectors and neuromorphic applications are fully introduced. Finally, the future perspectives and challenges of the low‐dimensional nanomaterials based photodetectors are also discussed. 

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5. Physics-Based Device Models and Progress Review for Active Piezoelectric Semiconductor Devices

   https://doi.org/10.3390/s20143872  

   Oh, Hongseok; Dayeh, Shadi A. (July 2020, Sensors)

   Piezoelectric devices transduce mechanical energy to electrical energy by elastic deformation, which distorts local dipoles in crystalline materials. Amongst electromechanical sensors, piezoelectric devices are advantageous because of their scalability, light weight, low power consumption, and readily built-in amplification and ability for multiplexing, which are essential for wearables, medical devices, and robotics. This paper reviews recent progress in active piezoelectric devices. We classify these piezoelectric devices according to the material dimensionality and present physics-based device models to describe and quantify the piezoelectric response for one-dimensional nanowires, emerging two-dimensional materials, and three-dimensional thin films. Different transduction mechanisms and state-of-the-art devices for each type of material are reviewed. Perspectives on the future applications of active piezoelectric devices are discussed. 

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