ABSTRACT Halide perovskites possess an intrinsically dynamic structure that strongly influences their electro‐optical performance and stability. Understanding how a microscopic phenomenon affects a global physical property is critical for better using these materials. Here, we suggest a new mechanism that explains synchronized electron–hole radiative recombination that extends over 10 µm well beyond the current understanding. The physical observable we follow is photoluminescence intermittencies in vapor grown, all‐inorganic halide perovskite crystals. This blinking effect is synchronized across distances well beyond the electron diffusion length, contradicting the widely accepted theory that assumes a “supertrap” involvement in photoluminescence intermittencies in halide perovskites. Such theories limit the range of synchronization of electron–hole radiative recombination by an order of magnitude to what we measure. We show beyond doubt a clear connection between the appearance of blinking and Pb‐rich growth conditions. Thus, the new framework puts the focus on hole diffusion to explain micron scale synchronization in halide perovskites.

ABSTRACT The mechanical mismatch between optogenetic implants and soft biological tissues greatly limits their in vivo performance, particularly in the precise modulation of neural circuits that undergo substantial deformation during spontaneous physiological activities. These challenges have long hindered stable and accurate optogenetic investigations of both the central and peripheral nervous systems in freely behaving animals. Here, we present a Wireless, Implantable, and Stretchable Device for Optogenetic Modulation (WISDOM), fabricated through a low‐cost and laboratory‐reproducible process. Inspired by the tendril mechanics of climbing plants, WISDOM integrates a 3D helical stretchable interconnect structure, endowing the device with exceptional stretchability of up to 91%. Weighing only 0.85 g, WISDOM exhibits excellent encapsulation stability, mechanical robustness, and well‐controlled thermal performance, enabling fully implantable and untethered optogenetic modulation in free‐moving rodents. Moreover, its customizable µ‐LED architecture supports site‐specific, multi‐site, and patterned surface stimulation, allowing precise modulation across the brain, peripheral nerves, and visceral organs. Overall, WISDOM provides a versatile and long‐term stable platform for precise regulation of neural activity throughout the entire organism, offering transformative potential for future diagnostic and therapeutic strategies targeting neurological, cardiovascular, and metabolic disorders.

ABSTRACT Precise control of temperature fields at the micro‐ and nanoscale is essential for emerging applications in nanophotonics, catalysis, and microfluidics, yet remains difficult due to the diffusive nature of heat. While inverse‐design algorithms have advanced thermoplasmonic metasurfaces, their extension to all‐dielectric systems has not been explored. Here, an inverse thermal design framework is introduced for dielectric metasurfaces composed of thermo‐optical amorphous silicon (a‐Si) nanoresonators. By leveraging a precomputed library of absorption spectra as a function of geometry and temperature, target thermal profiles are directly mapped onto metasurfaces, enabling both uniform and complex temperature shaping. Unlike plasmonic platforms that require multi‐resonator unit cells for tunability, dielectric nanoresonators provide intrinsic reconfigurability. At wavelengths where the thermo‐optical coefficient is negligible (e.g., ∼500 nm), absorption remains temperature‐invariant, whereas at other wavelengths it becomes strongly temperature‐dependent, allowing illumination intensity to reshape the thermal landscape. This multifunctionality permits a single metasurface to yield distinct profiles under different excitation conditions without added structural complexity. As a proof of concept, photothermal catalysis on such metasurfaces is modeled, predicting over 30% enhancement in reaction rates. The presented framework establishes a scalable strategy for engineering nanoscale temperature fields with broad implications for catalysis, thermal management, and photothermal energy conversion.

ABSTRACT High‐brightness, full‐color microdisplays with sub‐5 µm pixel pitch are key for next‐generation augmented and virtual reality applications. While blue InGaN/GaN µLEDs offer excellent luminance, the integration of efficient red and green emission remains a major challenge in the realization of full color microLED displays. Using color converters such as quantum dots or perovskites is a promising approach, but current pixelation methods for these nanomaterials often suffer from limited resolution, significant material waste, and optical degradation during or after the process. Herein, we introduce a scalable directed‐assembly method for fabricating red‐ and green‐converter 3D micro‐subpixels based on pure colloidal quantum nanoplatelets. This method, compatible with non‐polar solvent dispersions, enables the high‐resolution fabrication of micro‐subpixels of 3.5 µm (corresponding to ∼3000 PPI in RGB configuration) in width and over 1.3 µm in thickness, achieving more than 75% blue light absorption efficiency without requiring much thicker polymer matrices or nanocomposites. Integration on 8 µm × 8 µm InGaN/GaN µLED arrays demonstrates homogeneous large‐area coverage, high structural fidelity, and promising electro‐optical performance with external photoluminescent quantum yield of red micro‐subpixel reaching ∼71%. The process is compatible with 200 mm CMOS‐type processes and offers a compelling pathway toward next‐generation high‐brightness, high‐resolution full‐color microdisplays.

ABSTRACT Effective regulation of optical and thermal properties remains a crucial challenge for materials in variable temperature environments. Conventional thermal control materials, characterized by static thermo‐optical properties, often fail to meet the demands under dynamic thermal conditions. In this study, we achieve exceptional thermo‐optical properties in AgNbO 3 ‐based ceramics (Ag 1‐x Bi x/3 NbO 3 with x = 0.20, ABN0.20), demonstrating a high emittance variation (Δε = 0.298) and temperature‐stable absorptance (Δα = 0.046) across a broad temperature range. Through integrated experimental analysis and DFT calculations, we investigate the effects of doping on lattice structure, phase transition temperature, and thermo‐optical properties. Key findings include: (i) The phase transition temperature decreases with decreasing ionic radius of the dopant, particularly that Bi 3+ and Ta 5+ ion doping significantly lowers the M 1 –M 2 phase transition temperature, stabilizing the antiferroelectric phase near room temperature. (ii) Dopants effectively narrow the bandgap of AgNbO 3 , enhancing solar absorption. (iii) The d–p orbital hybridization between Ag(Nb)─O bonds governs emissivity through thermal disruption susceptibility. Strengthened hybridization expands the resonant area, thereby increasing infrared emission. These results demonstrate that orbital hybridization‐mediated tuning in doped AgNbO 3 ceramics offers a promising pathway for developing adaptive thermal control systems, particularly for applications requiring real‐time emissivity modulation and solar‐thermal regulation.

Abstract Active manipulation of light–matter interaction at the nanoscale, especially in the strong coupling regime, is critical for advanced biochemical and optical applications. However, simultaneous control over multiple degrees of freedom such as spin‐valley and chirality, remains challenging because the weak bonding among them. Here, a compact Au@Ag nanorod/ J‐aggregates/WS 2 heterocavity is proposed, which enables not only valley polarization manipulation but also tunable Raman enhancement at room temperature. Two species of excitons, from both the K/K' valleys in the WS 2 monolayer and the chiral J‐aggregates, are coupled with a single nanocavity mode exhibiting pronounced double Rabi splittings (142 and 130 meV). Utilizing the plasmon–biexciton strong coupling effect, a degree of circular polarization (DCP) reaching up to 46% is achieved, which is among the largest values reported for room‐temperature operation. And detuning‐dependent Raman enhancements ranging from 10 4 to 10 7 has also been observed. Theoretical research reveals that mirror‐symmetry breaking induced by the chiral J‐aggregates and inclined Au@Ag nanocavity lifts the degeneracy between σ + and σ − plexciton modes, which causes the pronounced valley‐selective emission. Meanwhile, valley‐polarized excitons can subsequently reshapes the near‐field distribution, yielding tunable Raman enhancement from the same nanocavity. These results open rich possibilities toward multifunctional plasmon‐enhanced spectroscopy, chiral light–matter interfaces, and integrated nanophotonic devices.

ABSTRACT The development of high‐performance, universal stimuli‐responsive materials is hindered by the disconnect between fundamental design principles and macroscopic multifunctionality. Herein, we report an atomically precise copper nanocluster Cu 16 , engineered with the dual alkynyl/perfluorocarboxylate ligands to simultaneously control molecular and supramolecular assembly. Endowed with ambient ultrastability and ultrabright luminescence, Cu 16 undergoes well‐defined, stimuli‐induced changes that produce distinct, high‐contrast responses to five functionally independent stimuli. Systematic studies reveal that Cu 16 operates through a dual‐channel responsive mechanism, where the structural channel governs responses to volatile organic compounds and pressure via structural perturbations at different extents, and the luminescent channel mediates responses to temperature, O 2 , and X‐ray radiation via distinct electronic state transitions. The orthogonal discrimination of five stimuli yields quintuple optical switching effects, which not only establishes Cu 16 as a state‐of‐the‐art stimuli‐responsive metal cluster with multidimensional signaling capability, but also confers unprecedented functional breadth. This work provides an atomic‐precision blueprint to engineer advanced stimuli‐responsive materials with multifunctionality, revealing explicit synthesis–structure–property correlations to guide the development of next‐generation programmable smart materials.

ABSTRACT Three classes of mid‐infrared metasurfaces operating in the 12–24 µm spectral range are produced solely through the structuration of a single‐crystal silicon surface. By controlling surface topography, we achieve tailorable spectral responses, including resonant, broadband, and anti‐resonant absorptance. Two metasurfaces use smooth gratings, while the third employs a hierarchical topography involving further nanostructuration, leading to a rough grating. Simulations and experiments reveal distinct spectral behaviors: (i) narrow‐band absorptance with mid‐quality factor and angle‐tunable resonant wavelength, also enabling precise control over the photon lifetime, (ii) broadband absorptance, and (iii) broadband absorptance with narrow‐band anti‐resonant absorption dip. Compared to flat silicon surfaces, these metasurfaces enable significantly enhanced light‐matter interactions, achieving a two‐fold increase in the absorptance with only 10% increase in effective surface area. The observed effects are attributed to different expressions of Wood anomalies, driven by the high carrier concentration in heavily doped silicon, which critically shape the metasurfaces’ optical behavior.

ABSTRACT Bio‐inspired optical neuromorphic systems are a frontier in developing high‐speed, low‐energy visual intelligence processors. However, conventional electrical synapses face challenges like high energy consumption and photoelectric conversion bottlenecks. Here, we discuss leveraging ferroelectrics to realize all‐optical synaptic devices as an innovative path toward zero electrical energy brain‐like computing. Optical pulses can generate the non‐volatile bulk photovoltaic effect (BPVE) and light‐induced polarization switching, inducing ferroelectrics to generate non‐equilibrium photogenerated carrier capture and release to achieve synaptic current. This signal directly serves as the post‐synaptic potential without external bias, simulating synaptic behavior. As the entire process is driven solely by light pulses, eliminating complex electrical interconnects and write operations, it removes Ohmic losses and static power consumption, achieving zero static power for information storage. These all‐optical synapses are anticipated to overcome the “power wall”, providing a possible solution path for addressing the huge energy consumption problem caused by the explosive growth of current artificial intelligence computing power demands.

ABSTRACT Silicon avalanche photodiodes (APDs) exhibit excellent performance, including high speed, high responsivity, and high sensitivity in amplification of optical signals by virtue of avalanche multiplication effect, which holds considerable importance in weak light detection. Here, a systematic review on the research progress of Si‐APDs is presented. First, the typical device structures and working mechanisms of Si‐APDs are introduced. Subsequently, the optimizations of structural design and fabrication processes of Si‐APDs, as well as their impacts on the performance, are discussed. Finally, the present challenges and future development trends of Si‐APDs are prospected.