Mingming Jiang

The pursuit of a monolithic semiconductor platform capable of simultaneously delivering polarized ultraviolet detection and efficient high-energy X-ray detection remains a fundamental challenge, due to the mutually exclusive requirements of strong structural anisotropy, high atomic density, and long-term environmental stability. Here, we break this longstanding trade-off by developing high-quality one-dimensional RbCu ₂ I ₃ single-crystals, a lead-free perovskite derivative that intrinsically combines a wide direct bandgap (∼3.85 eV ), a highly anisotropic crystal framework, a high effective atomic number ( Z - avg ≈46.7), and an exceptional mobility-lifetime (μτ) of 8.8×10 ⁻⁴ cm ² V ⁻¹ product. In a single device architecture, the material enables dual-function operation: as a polarization-sensitive ultraviolet photodetector, it achieves an exceptional polarization ratio of 9.26, a responsivity of 588 mA/W, a specific detectivity of 8.7×10 ¹² Jones, and fast response times of 338/389 μs at 310 nm; concurrently, as a direct X-ray detector, it delivers a record sensitivity of 60,185 μC Gy ⁻¹ cm ⁻² , an ultralow detection limit of 20.4 nGy s ⁻¹ , and high-resolution X-ray imaging. Remarkably, the unencapsulated devices exhibit robustness and excellent air stability over months. This work represents a disruptive advance beyond the conventional paradigm of material-level segregation, establishing a new route toward compact, stable, and multifunctional optoelectronic systems for next-generation imaging and sensing.

Self-powered photodetectors are indispensable for low-power optoelectronic systems such as edge sensing, optical communication, and machine vision. However, their development is severely hampered by interfacial defects that induce carrier leakage and nonradiative recombination. Here, we overcome this challenge by designing a WSe2/GaSb van der Waals (vdW) heterojunction with favorable band alignment and a strong built-in electric field at the interface. The device delivers an ultralow dark current of ~ 2 pA at zero bias and a rectification ratio exceeding 104, enabling zero-bias operation across 210–1000 nm. Under 880 nm illumination, it exhibits a responsivity of 331.5 mA·W−1, a specific detectivity of 1.38 ×1012 Jones, an open-circuit voltage of 0.52 V, a maximum output power of 1.66 nW, and fast rise/fall times of 431/356 μs. Beyond device-level metrics, we demonstrate a closed “sensing−communication−computing” loop by realizing 8-bit ASCII optical communication and low-power near-infrared traffic sign recognition. Using U-Net reconstruction and YOLOv8n classification, the recognition accuracy is boosted from ~ 30% to ~ 80%, confirming its practical utility. This work provides an experimental and theoretical pathway toward next-generation self-powered, low-noise, intelligent vdW heterojunction photodetectors.

Polarization-sensitive self-powered ultraviolet photodetectors are of great significance for advanced target recognition, machine vision, and artificial intelligence, particularly in complex optical environments where multidimensional information extraction is critical. We report a self-powered photodetector exploiting a RbCu2I3/SiC heterojunction, which affords concurrent ultraviolet spectral discrimination and polarization-resolved detection without external bias. At zero bias and 310 nm excitation, the device simultaneously achieves a light-to-dark-current ratio ∼106, a responsivity of 240 mA/W, a detectivity of 9 ×1013 Jones, a microsecond-scale transient response (τrise/τfall = 315/515 μs), and an exceptional dichroic ratio of 8.9. Collectively, these specifications establish a new performance benchmark, significantly surpassing not only commercially available all-inorganic photodetectors but also the most advanced laboratory-scale counterparts reported to date. The superior photodetection of RbCu2I3/SiC originates from the synergistic interplay of RbCu2I3's intrinsic anisotropic carrier mobility and favorable type-II band alignment, which together yield an ultralow dark current (nA-level), a high rectification ratio (∼104), and efficient spatial separation and unidirectional transport of photocarriers. Leveraging these advantages, we further demonstrate a polarization-resolved image encryption–decryption system integrated with a convolutional neural network, achieving a decryption accuracy of 98.1%. This work highlights the transformative potential of RbCu2I3/SiC heterostructures for next-generation multifunctional optoelectronics and secure optical communication, opening new avenues for intelligent photonic systems.

Bipolar photoresponse photodetectors enable spectral discrimination and optical logic, but conventional devices often suffer from poor stability and complex fabrication. Here, we report a fully solid-state, chip-scale BaTiO ₃ /ZnO heterojunction photodetector with a simple structure, compact size, and precise wavelength discrimination. Under self-powered operation, it selectively detects 330 nm and 395 nm light with positive and negative photocurrents, showing responsivities of 6.7 and −26.1 mA/W, respectively. Fast response and narrow wavelength selectivity (∼67 nm) are achieved via optimized pyroelectric current regulation. The interplay between the photovoltaic effect in the heterojunction and the polarization of the BaTiO ₃ is investigated. Finally, a 5 × 5 BaTiO ₃ /ZnO array was further demonstrated for encrypted imaging. This work presents a compact, high-performance platform for precise light-wavelength discrimination, optical logic, and secure optical communication.

Conventional neuromorphic vision systems suffer from architectural fragmentation, wherein sensing, memory, and processing are distributed across discrete modules, causing high latency, energy waste, and poor dynamic adaptability. Here, we present a wavelength-driven trimodal field-effect phototransistor (TriM-FEP) based on layered HfS2, which offers a new solution to this challenge. This single device integrates polarity-switchable photoresponses and synaptic dynamics without external bias or complex circuitry. By simply tuning the incident wavelength, the TriM-FEP delivers three distinct, dynamically switchable photoresponses: a synaptic-like photoresponse under solar-blind ultraviolet, fast negative photocurrent in the visible, and fast positive photocurrent in the near-infrared. Notably, this unique polarity reversal and speed variation are dominated by the photogating effect and the bolometric effect at different wavelengths, respectively. Beyond fundamental physics, the TriM-FEP enables real-time multichannel encrypted optical communication and in-sensor image preprocessing, eliminating the need for separate computing units. This work transcends the limitations of multicomponent cooperation, establishing a compact, energy-efficient platform that unifies sensing, memory, and processing at the device level.

The relentless demand for real‐time, high‐dimensional optical information processing is fundamentally hindered by the physical separation of sensing, storage, and computing in conventional architectures, which incurs prohibitive energy and latency overheads. Here, we break this paradigm by constructing a quasi‐one‐dimensional TiS ₃ /2H‐MoTe ₂ van der Waals heterostructure that intrinsically decouples and synergistically couples two distinct physical mechanisms of anisotropic carrier transport for polarization‐sensitive perception and ion migration/trapping for nonvolatile memory. This TiS ₃ /2H‐MoTe ₂ heterostructure simultaneously delivers self‐powered, near‐infrared polarization‐senstive photodetection with comparable performance (a dichroic ratio of 7.14, responsivity of 198 mA/W, detectivity of 6.9 × 10 ¹¹ Jones, and a fast 61/67 µs response at 1064 nm), alongside robust memristive switching behavior (ON/OFF ratio exceeding 10 ⁵ and retention >2300 s). The versatility is governed by decoupled driving forces of transient photogenerated carrier dynamics and persistent electric‐field‐driven ion and hole migration, enabling physically independent yet co‐located perception and memory channels. Beyond functional synergy, this platform executes a complete bioinspired cognitive chain, from threshold‐triggered nociception and injury‐induced sensitization to real‐time skylight‐polarization navigation, all within a single device. Our work transcends post‐processing compensation and functional additivity, establishing an intrinsic, intelligent paradigm for in‐sensor computing with immediate implications for edge AI, autonomous systems, and neuromorphic electronics.

Bulk photovoltaic effect (BPVE) enables self‐powered optoelectronics beyond the Shockley‐Queisser limit, yet high‐performance junction‐free near‐infrared (NIR) detectors remain elusive due to weak intrinsic non‐centrosymmetry and severe dark current in existing narrow‐gap semiconductors. Herein, we synthesize polar needle‐like GaSb single crystals via self‐catalyzed CVD, exploiting its 0.72 eV direct bandgap, uniform non‐centrosymmetric polarity, and high crystallinity to realize a zero‐bias GaSb field‐effect‐transistor (FET) architecture coupled with an ultra‐broad 210‐1800 nm photoresponse and ultralow ∼3 pA dark current. At 1550 nm and 100 mW/cm ² , five devices deliver a mean short‐circuit current density of 17.9 ± 12.0 mA/cm ² (increased up to 349.37 ± 191.75 mA/cm ² upon 10 W/cm ² illumination) and an effective bulk photovoltaic coefficient (β _eff ) of 0.18 ± 0.12 V ⁻¹ . Near a tiny −4 mV transition bias, switchable bipolar photoresponse yields an exceptional polarization‐current ratio approaching 300. Mechanistic studies verify that intrinsic shift current dominates the channel photocurrent, modulated by photon‐drag injection and local Dember effect. Beyond photodetection, we integrate GaSb FET with response‐guided computational imaging and a lightweight convolutional neural network, boosting letter‐recognition accuracy through scattering media from 63.8% to 99.4%. This work establishes GaSb as a transformative BPVE platform, advancing low‐power polarization‐resolved NIR intelligent perception by integrating material symmetry engineering, device physics, and computational imaging.

Conventional photodetectors dominated by a single physical effect are strictly constrained by the Shockley-Queisser limit, accompanied by intrinsic performance saturation, inadequate operational flexibility, and a complete absence of functions and secure functionalities. Here, we present large-area integrable Te/GaN heterostructure array devices fabricated from high-quality Te films via glancing-incidence physical vapor deposition. Benefiting from the intrinsic synergy between photovoltaic and photothermoelectric effects, these devices offer bias-free, position-programmable bipolar photoresponse. Under 365 nm illumination, the Te/GaN devices exhibit competitive figures of merit among similar devices, with positive/negative responsivity up to 308.4 mA/W and 54.5 mA/W, specific detectivity exceeding 1.09×1013 Jones and 7.52×1012 Jones, respectively, at zero bias. By using illumination position and response polarity as dual physical keys, the developed wafer-scale 20×20-pixel Te/GaN heteroarrays successfully implement reconfigurable image processing and encrypted image transmission, demonstrating unprecedented intelligent and physically secure functionalities for next-generation optoelectronic chips. This work overcomes the performance bottlenecks and limited operational degrees of freedom in single-effect devices, and achieves reliable, scalable array applications without external components, establishing a universal paradigm for high-performance, intelligent and secure integrated optoelectronics systems.

The monolithic integration of ultraviolet (UV) and near‐infrared (NIR) photodetection in a single device is fundamentally constrained by the inherent spectral crosstalk and architectural complexity of traditional heterostructures. Herein, we circumvent these limitations by introducing a paradigm‐shifting halide‐assisted defect‐compensation strategy that induces a semimetallic‐to‐semiconducting transition in topological 1T’‐MoTe ₂ , opening a tunable bandgap while preserving its intrinsically high carrier mobility. This material transformation enables a monolithic I‐1T’‐MoTe ₂ /GaN van der Waals heterojunction that achieves two mechanistically distinct, zero‐bias photodetection pathways within a single interface: a Schottky‐junction‐mediated UV response and a band‐engineered NIR absorption. The device delivers exceptional performance, including responsivities of 268 mA/W (350 nm) and 258 mA/W (750 nm), detectivities exceeding 10 ¹¹ Jones, and microsecond‐scale response speeds. Crucially, it overcomes the persistent trade‐off between high sensitivity and polarization discrimination, yielding a record polarization ratio of 8.55 in the NIR regime. We further validate its practical utility through robust demonstrations in encrypted optical communication and filter‐free multispectral imaging, underscoring its resilience and readiness for real‐world deployment. By establishing a material‐intrinsic route to programmable band‐structure engineering in topological systems, this work lays a transformative foundation for intelligent, polarization‐resolved photonic platforms and next‐generation secure sensing technologies.