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Self-powered solar-blind ultraviolet detection and integrated electroluminescence performance of Ga2O3:Er-based devices

Gallium oxide (Ga2O3) exhibits broad application prospects in solar-blind ultraviolet detection and rare-earth-activated electroluminescence (EL). However, the high-density intrinsic defects within Ga2O3 severely limit the development of high-performance photodetectors. Moreover, studies on dual-function devices integrating photodetection with EL remain scarce. Herein, we synthesized surface-wrinkled Er-doped Ga2O3 (Ga2O3:Er) films via thermal decomposition of organic precursors. This undulating morphology enhances the ultraviolet light absorption of films. Additionally, Er doping suppresses oxygen vacancies and modulates the heterojunction band alignment. The constructed self-powered photodetector exhibits a responsivity of ∼3.75 × 103 mA/W, a specific detectivity of ∼1.86 × 1013 Jones, and a response time of ∼30 μs under 254 nm illumination. Moreover, the device exhibits characteristic Er-related EL driven by trap-assisted tunneling mechanisms under high reverse bias. The integrated device has been demonstrated for applications in optical-electrical-optical signal conversion and multi-modal signal response.

Spring-integrated low-frequency ME resonator with strong coupling capability and low equivalent magnetic noise

Resonant magnetoelectric (ME) sensors offer the advantages of high sensitivity and inherent narrow-band filtering capability. However, the development of ultra-low-frequency (ULF) ME resonators combining high mechanical quality factor (Qm), low noise performance, and stable near-ideal boundary conditions remains a significant challenge. In this study, a spring-integrated ULF ME resonator is proposed and systematically investigated. The device consists of an elastic support layer, a piezoelectric layer, and a piezomagnetic layer. The elastic support layer incorporates two meander springs at both ends, creating quasi-free boundary conditions for the central sandwich-structured ME composite and enabling excitation of a high-order bending mode with a substantially reduced resonant frequency. Experimental results confirm the excitation of the third-order bending mode at a low frequency of 1266 Hz, with a calculated Qm of 144.8. In addition, the resonant ME coefficient reaches as high as 1633.5 V/(cm Oe), and the equivalent magnetic noise decreases to 300 fT/√Hz around the resonance frequency, demonstrating great potential for specific-frequency magnetic field detection applications, including signature current identification and underground cable tracing. More importantly, the spring-integrated resonant structure provides fixed boundary conditions and maintains a stable operating frequency during long-term operation.

Proteomics‐Driven Strategies for Proximity‐Inducing Drug Discovery

ABSTRACT In recent years, proximity‐inducing drugs have emerged as a novel therapeutic modality that induces or stabilizes protein‐protein interactions, especially by recruiting effector proteins to specific target proteins, thereby achieving functions beyond traditional inhibitors. The potential of proximity‐inducing drugs extends beyond targeted protein degradation (TPD), as studies have demonstrated their ability to regulate biological processes such as signal transduction, gene transcription, chromatin regulation, and protein trafficking by modulating protein interaction networks. Rational discovery of proximity‐inducing drugs requires clarifying their effects on protein‐protein interactions, determining drug selectivity, and developing suitable ligands for drug construction. Proteomics has become a central technology in drug discovery, enabling global identification of the direct drug targets and systematic characterization of proteome‐wide downstream responses. This provides a more refined map of drug mechanisms. In parallel, advances in machine learning applied to proteomic data, together with the expansion of proteome‐wide ligandability maps, are further accelerating the discovery and optimization of proximity‐inducing drugs. This review summarizes recent advances of proximity‐inducing drugs, with a particular emphasis on how proteomics facilitates target space expansion, drug efficacy optimization, and ligandability discovery, alongside the emerging contributions of machine learning. Collectively, these insights aim to support the rational development of next‐generation proximity‐inducing drugs.

Critical behavior of a novel layered ferromagnetic semiconductor Cr1.17Ga1.47Se4

Layered magnetic semiconductors have attracted considerable interest due to their rich magnetic properties and potential applications in low-dimensional spintronics. Here, we report a novel layered magnetic semiconductor, Cr1.17Ga1.47Se4, featuring CrGa2Se4 slabs interleaved with a partially occupied Cr layer. Transmission spectrum, electrical transport, and magnetization measurements reveal that Cr1.17Ga1.47Se4 is a ferromagnetic semiconductor with an optical bandgap of 1.12 eV and a Curie temperature of 34 K. A comprehensive analysis based on modified Arrott plots, the Kouvel–Fisher method, and scaling relations yields a self-consistent set of critical exponents, β  = 0.362, γ  = 1.381, and δ  = 4.81. These exponents are close to those obtained from renormalization group analysis, indicating that Cr1.17Ga1.47Se4 belongs to the three-dimensional Heisenberg system with long-range magnetic interactions. Our results provide a platform for exploring two-dimensional magnetic semiconductors and provide insights into the nature of magnetism of layered magnetic semiconductors.

Bandgap-dependent defect properties in mixed-halide perovskites

Defects in wide-bandgap perovskite solar cells critically limit device performance, yet their chemical nature and bandgap-dependent evolution remain insufficiently understood. Here, we investigate the defect properties of mixed-halide wide-bandgap perovskite solar cells with representative bandgaps of 1.67, 1.78, and 1.93 eV by systematically tuning the I/Br ratio while maintaining the same FA/Cs mixed-cation framework. Thermal admittance spectroscopy was employed to quantify the defect energy depth and defect-state density in these devices. The results reveal that the defect activation energy increases monotonically with increasing bandgap, indicating the formation of deeper defect states in Br-rich wide-bandgap perovskites. By using p-phenylenediamine diiodide to passivate iodide-vacancy-related defects, defect-mediated nonradiative recombination is significantly suppressed, leading to prolonged carrier lifetimes and improved device performance. These results suggest that iodide-vacancy-related halide defects are the dominant recombination-active defects in mixed-halide wide-bandgap perovskite solar cells. Notably, although iodide-vacancy passivation reduces defect density and improves device performance, its effectiveness gradually diminishes as the bandgap increases, highlighting the increasing difficulty of defect passivation in Br-rich wide-bandgap perovskites.

Unipolar ferroelectric synapses with subfemtojoule energy consumption

Neuromorphic computing demands artificial synapses that combine ultra-low energy consumption with simple modulation schemes. Here, we demonstrate unipolar ferroelectric tunnel junction synapse based on an Au/Cr/HZO/LSMO/STO heterostructure, in which both excitatory and inhibitory plasticity are realized solely by tuning the pulse width, without reversing voltage polarity. This unipolar operation further enables emulation of the Bienenstock–Cooper–Munro learning rule with an enhanced depression effect as well as perceptual functions such as edge detection. Pulse-width-modulated long-term potentiation was leveraged to experimentally emulate Pavlovian conditioning. Moreover, continuous long-term potentiation and long-term depression were achieved by alternately varying the pulse width and were applied to motion detection. This work provides a new pathway for implementing diverse neuromorphic functionalities through simple pulse-width modulation, highlighting the potential of unipolar ferroelectric synapses for efficient in-memory computing systems.

Theoretical strategy for coherent perfect absorption based on photonic time crystals: Interference and energy control

Photonic time crystals (PTCs) are artificial materials whose electromagnetic (EM) properties vary with time, enabling the realization of physical phenomena and energy conversion devices through the utilization of the time dimension. A theoretical strategy based on the PTCs for achieving coherent perfect absorption (CPA) is introduced in this Letter, enabling controllable switching between energy amplification (EA) and CPA. A single EM wave propagating within the PTC momentum bandgap absorbs pump energy and grows exponentially, thereby generating EA. Signal wave and control one generate coherent interference within the PTCs, enabling CPA by controlling the phase difference and intensity of the two waves. Further research reveals that increasing the PTCs' period effectively enhances performance of CPA, while altering the control wave's phase and intensity facilitate mutual switching between CPA and EA. The study employs theoretical calculations using the transfer matrix method to establish a PTC-based CPA strategy, while analyzing the generation processes of EA and CPA within the PTCs via the finite-difference time-domain method. This research expands the field of PTC studies, achieves controllable switching between PTC-based EA and CPA, and demonstrates the physical mechanism based on energy control, conversion, and EM wave interference within the PTCs.

Low optical loss electrical isolation for multi-section monolithic GaSb-based photonic circuits

Monolithic photonic integrated circuit (PIC) platforms exploiting III–V materials combine passive and active waveguide structures in multi-section optoelectronic device architectures. Their operation requires high electrical isolation between adjacent functional sections without compromising the optical signal. This fundamental requirement is addressed for GaSb-based waveguides, which are known to exhibit high conductivity of p-type layers, reducing the electrical isolation capability. To this end, a co-designed electrical–optical isolation strategy based on using deeply etched strip waveguides combined with adiabatic ridge-to-strip waveguide tapers in GaSb-based multiple-quantum well heterostructures is proposed. While deep etching alone enables isolation resistances of up to 40 kΩ, it severely degrades optical propagation. By introducing optimized adiabatic tapers, we demonstrate good optical performance as single mode continuous-wave lasing in a two-section device with integrated absorber, while maintaining an isolation resistance of 17.3 kΩ; this corresponds to an approximately 17-fold improvement over previously reported GaSb two-section devices. The approach establishes a critical building block for the development of monolithic GaSb-based PICs operating above 2 μm.

Parametric resonance and RF-to-THz frequency conversion in semiconductor plasmonic crystals

We show that plasma excitations in nanoscale field-effect transistor structures with periodically alternating gated and ungated regions (plasmonic crystals) exhibit a band structure with finite curvature (effective mass), in contrast to the linear and square-root dispersions of gated and ungated plasmons. These modes can be excited by synchronous gate-voltage pumping, avoiding the spatial nonuniformities of current-driven excitation. When the modulation drives the gated regions across threshold, the system enters a strongly nonlinear regime in which periodic modulation of the channel capacitance provides a parametric drive described by a generalized Mathieu equation. Depending on damping, this leads to either damped response or parametric instability. The resulting nonlinear dynamics generates a broad harmonic spectrum, enabling RF-to-THz frequency upconversion. Estimated drive conditions are compatible with existing millimeter-wave sources, including Schottky-diode multiplier chains and Gunn-diode oscillators.

Prediction of mass spectra using large chemical language models and verification of adaptability in data-scarce domains

Machine learning methods for predicting the electron ionization mass spectra from molecular structures have shown promise for environmental chemical identification, but their performance under domain-specific data scarcity remains poorly understood. We systematically compare a conventional multilayer perceptron model (NEIMS) with a Transformer-based chemical foundation model (MolFormer-XL) for the electron ionization mass spectrometry spectrum prediction under controlled few-shot conditions. Using fluorine-containing molecules as a broader proxy domain, including a PFAS-like subset, motivated by the practical challenge of detecting novel fluorinated contaminants with limited reference data, we vary the number of domain-specific training examples from 5 to 175 while maintaining fixed validation and test sets. Across all few-shot conditions and three of four evaluation metrics (weighted cosine similarity, intensity-weighted precision, and top-10 precision), MolFormer-XL consistently outperforms NEIMS, while intensity-weighted recall remains comparable between the two models. The largest performance gaps are observed in extreme data-scarcity regimes. These results demonstrate that MolFormer-XL, which combines pre-trained molecular representations with a Transformer-based architecture and learned SMILES embeddings, provides a promising approach for transfer under severe domain-specific data scarcity in environmental mass spectrometry.

Defect engineering via O-Se co-treatment enabled high-performance self-powered Au/O-Se MoS2/In photodetector

Self-powered photodetectors (SPPDs) are essential for energy-self-sufficient optical imaging and optical communication applications. However, the defects generated in two-dimensional transition metal dichalcogenides lead to Fermi-level pinning at metal–semiconductor interfaces and non-radiative recombination of carriers, thereby seriously degrading the performance of SPPDs. The traditional defect engineering predominantly relies on single-atom passivation strategies, which essentially target a single type of defect, making it difficult to suppress multiple defect states located at different energy levels. Herein, we demonstrate a sequential multi-atom cooperative defect repair strategy in MoS2, which simultaneously repairs multiple defect states associated with sulfur vacancies within a single material. As a result, the Au/O-Se MoS2/In photodetector exhibits a high responsivity of 0.21 A/W, together with an ultrafast response speed of 720 ns under zero bias voltage. The device achieves high-fidelity optical imaging and reliable optical communication under self-powered operation. This work establishes a universal strategy for defect control through multi-atom cooperative effects, providing an avenue for achieving high photoelectric conversion in next-generation optoelectronic devices.

Outside Front Cover: Rediscovering Sodium Ionophores as Selective Agents for Lithium Recognition and Extraction (Angew. Chem. Int. Ed. 32/2026)

Electrostatically confined charge transport in split-gated MoS2 device

As semiconductor scaling approaches the quantum limit, transport phenomena increasingly deviate from classical behavior, necessitating the development of electrostatically defined low-dimensional architectures. Here, we demonstrate one-dimensional (1D)-like charge transport in a gate-defined quantum point contact based on a hexagonal boron nitride (h-BN)-encapsulated few-layer molybdenum disulfide (MoS2) device at cryogenic temperatures. The device exhibits an electron mobility of ∼6600 cm2 V−1 s−1 at 4.2 K, reflecting minimized disorder and a pristine heterostructure interface. A global back-gate controls the carrier density and reduces contact resistance via electrostatic doping at the contacts, while a local top-gate tunes the channel potential. Bottom split gates define a laterally confined conduction channel that can be continuously tuned to pinch-off, enabling precise control of carrier confinement. The observed transport characteristics reveal a transition from two-dimensional to 1D-like transport. These results highlight the potential of multi-gate MoS2 heterostructures for gate-defined quantum devices.

Wet-spinning vanadium oxide-based coaxial fibers for the construction of zinc-ion batteries

Fiber-shaped aqueous zinc-ion batteries (FAZIBs) emerge as a promising energy storage device for future wearable electronics. Vanadium-based oxides possess high theoretical capacity, benefiting from their multiple oxidation states and versatile open-framework structures, yet its practical application is largely hindered by the poor electrical conductivity and cycling instability. Herein, we develop a core–sheath fiber as a cathode for FAZIBs via coaxial wet-spinning. The incorporation of reduced graphene oxide (rGO) significantly enhances electron transport in the V2O3 core, while the utilization of holey rGO (HrGO) as a sheath guarantees rapid ion diffusion at the same time renders further mechanical and electrical supports. The obtained V2O3/rGO@HrGO fiber exhibits a high volumetric capacity of 429 mAh cm−3 at 0.4 A cm−3 and still retains 275 mAh cm−3 at 4.0 A cm−3 with improved stability. This study provides an alternative option for the design of a high performance fiber cathode for future wearable aqueous ZIBs.

Toroidal quasi-dark supermodes in microwave dielectric metasurfaces

We report a class of dielectric metasurfaces that support quasi-dark microwave resonances with tailored toroidal and antitoroidal field profiles. The metasurfaces are realized using quadrumers of high-permittivity and low-loss ceramic disk resonators as elementary building blocks, assembled on laser-processed dielectric foam substrates. The physical origin and symmetry properties of the supported modes are elucidated through group-theoretical analysis and validated by eigenfrequency and full-wave finite-element simulations. Experimental measurements confirm the existence of quasi-dark resonances with suppressed radiation losses. Owing to its generic and scalable design strategy, this approach can be readily extended to a broad range of dielectric metasurfaces composed of ceramic Mie resonators. The demonstrated metasurfaces provide a versatile platform for low-profile and strongly resonant devices, e.g., for sensing or narrowband filtering.

Synergistic effect of waste sisal fiber-derived carbon and graphene oxide for performance enhancement of sulfur-based thermally regenerative batteries

Sulfur-based thermally regenerative batteries (STRBs) offer a promising approach for low-grade waste heat recovery. To enhance their power output, we develop a sulfur electrode using a composite of sisal fiber-derived activated carbon (SFAC) with a porous structure and graphene oxide (GO) from waste biomass. The SFAC framework enhances the electrochemically active surface area while simultaneously reducing electron transport resistance, thereby boosting overall electrode performance. The incorporation of GO improves hydrophilicity and ion transport. The synergy between the two components significantly boosts power density and cycling stability. The STRB with the SFAC-GO@S electrode achieves a maximum power density of 56.9 W m−2, which is 57.6% higher than that of a bare carbon cloth-based sulfur electrode. The GO encapsulating effect on sulfur particles within SFAC pores yields a capacity retention of 89.6% after 30 cycles. An optimal GO concentration of 1.5 mg ml−1 gives the highest power density of 70.7 W m−2. Excessive GO causes agglomeration and blocks ion transport, degrading performance.

High-performance phototransistors based on heterojunctions of organic semiconductors and 2D perovskite single crystals

Two-dimensional (2D) organic–inorganic hybrid perovskites are promising candidates for optoelectronic applications owing to their excellent optoelectronic properties and enhanced stability compared to their three-dimensional counterparts. However, the optoelectronic performance of 2D perovskite single crystals is often constrained by low charge transport efficiency. Herein, we fabricated a (PEA)2PbI4/PDVT-10 heterojunction and corresponding phototransistor by transferring a mechanically exfoliated (PEA)2PbI4 single crystal onto a PDVT-10 film. This design strategically combines the exceptional light-harvesting ability of the perovskite with the high charge carrier mobility and gate tunability of the organic semiconductor. As a result, the concerted action of the photoconductive and field effects within the heterojunction yields outstanding photodetection metrics. Compared to the PDVT-10 device, the (PEA)2PbI4/PDVT-10 device shows a twofold improvement in photosensitivity (Ilight/Idark ∼ 1.1 × 103 @ 64 mW cm−2), a nearly three-order-of-magnitude increase in photocurrent, and a 32-fold higher responsivity (0.65 A W−1, @ 0.01 mW cm−2). This study provides a viable strategy for integrating the superior properties of perovskite single crystals and organic semiconductors to fabricate high-performance photodetectors.

High quantum-efficiency InGaAs/InP photodiodes heterogeneously integrated on SiN waveguides

The integration of photodiodes with optical waveguides is increasingly important for photonic integrated circuit development. We report modified uni-traveling-carrier photodiodes heterogeneously integrated onto Si3N4 optical waveguides, achieving quantum efficiencies up to 91% at 1550 nm. The combination of high quantum efficiencies and ultra-low dark currents yields high signal-to-noise ratios over a broad range of optical signal powers.

Constraints on atomistic disorder for scalable electron spin shuttling

Electron spin shuttling—the gate-controlled, coherent transport of electrons between qubit registers—increases qubit connectivity and enables efficient quantum-error-correction schemes. It is emerging as a key enabler of scalable silicon spin-qubit quantum computing. As an electron travels over micrometers, it encounters angstrom-scale disorder, causing fluctuations in its confinement potential, valley splitting, and valley phase. These lead to leakage into the valley-excited state, limiting high-fidelity shuttling speeds. Accurate predictions of shuttling fidelities thus require modeling tools that link atomistic and mesoscopic physics. We develop a multiscale simulation workflow to quantify these effects in the experimentally realized Si/SiGe “QuBus” conveyor-belt architecture. First, we resolve the time-dependent, gate-controlled device electrostatics by solving the Poisson equation using the finite-element method. Second, we construct conveyor-belt atomic structures with realistic atomistic disorder (random alloying and interface roughness); we resolve strain atomistically using the Keating valence force-field model. Third, we perform position-tracked atomistic tight-binding simulations of the shuttled electrons to obtain their time-dependent valley splittings and phases. Finally, these time traces parametrize a time-dependent Schrödinger equation, which we solve to predict valley dynamics. We find that interface roughness strongly suppresses shuttling fidelities, with a sharp anomaly near the atomic-layer scale. Overall, our predictions set practical, quantitative guidelines to realize scalable, high-fidelity shuttling in silicon spin-qubit architectures.

Internal-loss-limited 5.5% wall-plug efficiency in index-guided AlGaN UV-B laser diodes with polarization-doped cladding layers

This study identifies the dominant factor governing wall-plug efficiency (WPE) in AlGaN-based UV-B laser diodes. While previous studies have mainly focused on optical confinement, the limiting mechanism has remained unclear. Here, we investigate index-guided ridge waveguide laser diodes and systematically analyze the relationship between internal optical loss (αi) and device performance. Index-guided operation is confirmed by effective index simulations and near-field measurements. We find that device performance is governed primarily by αi rather than optical confinement. By minimizing αi, the threshold current is reduced, and the slope efficiency is improved, leading to a maximum WPE of 5.5% in an uncoated device. These results reveal that reducing αi, rather than enhancing optical confinement, is the key design principle for improving WPE in AlGaN-based UV-B laser diodes.