Detecting the chirality of molecules is of great importance in optics, biomedicine, and materials science. In chiroptical spectroscopy, it's crucial to achieve strong chiroptical signals with a minimal number of chiral molecules. The molecular chiroptical signals, however, are typically weak for chiral molecular sensing in conventional circular dichroism using photonic spin angular momentum, even in the presence of a large number of chiral molecules (micromoles to millimoles). Here, by involving chiral light-matter interaction with photonic orbital angular momentum, we demonstrate strong chiroptical responses that reflect the molecular chirality in a single chiral nanoassembly. We experimentally present the helical dichroism spectra of chiral nanoassemblies synthesized from L/D-cystines, consistent with electromagnetic simulations. The asymmetry factors in the fundamental wavelength and photoluminescence emission reach values of 0.53 and 1.18, respectively, exceeding those observed in the circular dichroism mechanism. To improve the dimensions of helical dichroism spectroscopy, we analyze helical dichroism in wavelength domain, polarization domain, and momentum space. Our findings not only expand the methods for trace chiral molecular sensing but also provide insights into chiral light-matter interactions.

Rock-paper-scissors interactions enable thermal localization to advance thermal metamaterials.

Ultra-wide bandgap gallium oxides offer tremendous possibilities to develop short-wave optoelectronic devices. However, it is formidably challenging to produce single-crystal gallium oxide wafer and develop high-performance high-dimensional optoelectronics. Here we show a liquid-metal-assisted strategy to directly synthesize and transfer single-crystal, large-area and ultrathin β-Ga2O3. Benefiting from the UV-exposure oxidation of liquid gallium and strong interaction with gallium, our β-Ga2O3 film shows a 4-inch wafer-scale size, a 7.5-nm thickness and a flexible transfer operation. The solar-blind β-Ga2O3 detector achieves high responsivity (16.3 A W-1), fast response (<150 μs) and wide linear dynamic range (120 dB). By employing metasurface design, the anisotropy ratio reaches a record high value of 28.8 for Ga2O3-based detectors. Moreover, we develop a sundial-inspired metasystem to simultaneously detect the incident direction, polarization, and intensity of solar-blind irradiation. These findings illustrate the potential of high-quality Ga2O3 wafer for high-dimensional photodetection, paving the way for next-generation solar-blind communications.

Radiative thermoregulatory textiles control thermal emission without continuous energy input, offering a sustainable route to personal thermal comfort and energy savings. However, it remains challenging for such textiles to autonomously respond to complex or rapid environmental changes while maintaining comfort across wide temperature fluctuations. Here, we develop a scalable, adaptive, and self-automated thermoregulatory meta-textile (ASTM) system by integrating a reconfigurable metallic–polymer meta-textile with sensing, control, and actuation modules. The mechanically reconfigurable metafiber architecture provides large and continuous infrared emissivity modulation, while the closed-loop control system enables automatic adaptation to environmental changes without human intervention. The ASTM expands the thermal comfort zone by 16.5 °C and maintains a stable temperature range of 20–26.7 °C during outdoor temperature fluctuations of up to 23.4 °C. Building energy simulations show that the meta-textile can achieve an average annual heating and cooling energy savings of 515 MJ m−2 across global climates, with notable CO2 reduction potential. This work demonstrates a system-integrated strategy for smart thermoregulatory textiles and provides a practical route toward personalized thermal comfort and energy-efficient building envelopes.

Light beams carrying orbital angular momentum (OAM) possess an unbounded set of orthogonal modes, offering significant potential for optical communication and security. However, exploiting OAM beams in space has been hindered by the lack of a versatile design toolkit. Here, we demonstrate a strategy to tailor OAM across multiple transverse planes by shaping optical caustics leveraging on catastrophe theory. With 3D-printed metasurfaces fabricated using two-photon polymerization lithography, we construct these caustics to steer Poynting vectors and achieve arbitrary shapes of OAM beams. Interestingly, we further realize "hidden" OAM along the propagation trajectory, where the intensity of the beam is spread out thus avoiding detection. By exploiting this intrinsic nature of OAM, we demonstrate the detection of encoded information in optical encryption. Our approach provides a unique framework for dynamic control of OAM in space, with promising applications in optical trapping and sensing, high-capacity data storage, and optical information security.

Optical frequency combs have received increasing attention, thanks to their fundamental importance in optical computing, communications, and metrology. Recently, acoustic frequency combs have been achieved, with several hundred comb teeth and a high-frequency range of over 100 kHz. Here, we report how to achieve an acoustic frequency comb with phonon lasers, featuring not only the record tooth number of 6000 and a tunable tooth spacing from 10 Hz to 100 kHz but also the ultrabroad bandwidth, spanning six orders of magnitude. In this device, two kinds of nonlinear couplings can emerge, i.e., gain-assisted light-motion coupling and cascaded four-wave mixing. Their interplay can be flexibly tuned by driving different vibration modes of the membrane. Therefore, a switch between a multi-color phonon laser and a phonon laser frequency comb is achievable. We provide the first step toward developing various phonon laser combs for potential applications in underwater sensing, flaw detection, and biomedical ultrasonics, with the help of phonon lasers, which have already been achieved in a wide range of systems such as membranes, photonic crystals, semiconductor lattices, cold ions, and levitated objects.

Nontrivial nearfield topologies in nano-optics refer to nearfield configurations embedded within singularities or topological defects, providing an ideal platform to explore integrated optoelectronics and higher-dimensional topological physics. Exciting such field topologies relies on selection rules related to various conserved quantities. Unfortunately, existing algebraic rules focus primarily on scalar singularities in nano-optical (e.g., plasmonic) systems and largely neglect the vectorial nature of the fields. More critically, these rules remain phenomenological. Given the intrinsic link between conserved quantities and symmetries, here we establish a unified selection rule using group theory that govern the excitations of nontrivial field topologies across three photonic spin states in generic nanophotonic systems. This rule can act as building blocks for constructing selection rules for exciting and engineering higher-dimensional field topologies (embedded within vectorial singularities and quasiparticles). These rules are derived purely from symmetry arguments and are therefore rooted in first principles. The proposed rules further predict two novel physical effects in plasmonic systems: spin-orbit splitting of vortices and multidimensional nested vortices. Phase-resolved in-situ measurements of nested multidimensional plasmonic topologies well demonstrate our findings. Our group-theory-based approach can serve as a versatile framework for engineering symmetry- and singularity-related phenomena-like circular meron lattices and plasmonic quasicrystals-in diverse wave systems.

Achieving magnetically switchable chiral light emission is an important goal for 2D opto-spintronics. However, conventional strategies face a fundamental trade-off between dynamic tunability and polarization contrast. Nonlinear optics, particularly the emerging mechanism of chiral second-harmonic generation (SHG), offers a distinct strategy to bypass this restriction, yet its experimental realization remains elusive due to stringent symmetry requirements. Here, we report giant nonlinear optical magnetochirality in a centrosymmetric 2D ferrotoroid, bilayer (2L) CrSBr. We reveal that a field-induced spin-canting state breaks the parity-time (PT) symmetry of the unperturbed antiferromagnetic (AFM) ground state, activating a spin-chirality-driven i-type susceptibility. The coherent interference between this emergent i-type and intrinsic c-type SHG susceptibilities generates a macroscopic circularly polarized SHG signal whose helicity is magnetically switchable. Leveraging this sensitive mechanism, we uncover remanent magnetic states after field saturation that evade conventional linear probes. By exploiting the non-volatility of these states, we demonstrate magneto-optical memory and logic operations. Our work establishes a general symmetry-driven strategy for tailoring nonlinear magnetochirality, while providing a sensitive optical probe for subtle spin textures in the 2D limit.

Parity-time symmetry has revolutionized wave and energy transport control in non-Hermitian systems, yet has so far been mostly explored in static phases, where a system's behaviour is locked into a fixed-symmetric or broken-symmetry phase. The vast potential of time-domain dynamics has remained largely untapped. Here we introduce the concept of temporal anti-parity-time symmetry, a principle that allows the transport dynamics of a system to be actively shaped in real time. Rather than designing static phases, we influence the timing of non-Hermitian phase transitions, making the system's temporal evolution itself a programmable degree of freedom. Through the dynamic control of material properties and convective flow, we dictate the exact moments these transitions occur, thereby controlling the entire transport history of the system. This temporal control achieves highly tunable field localization and realizes counterintuitive thermal transport, enabling temperature profiles to move forwards with convection, backwards against it or remain trapped at arbitrary locations. Our findings extend non-Hermitian physics into the time domain and establish a framework for on-demand wave and energy transport.

The imaginary Poynting momentum (IPM), as an intrinsic yet mysterious property of light, is nearly as ubiquitous as its real counterpart. However, prior research has only traced its origin to intensity asymmetry and showcased its capability in particle manipulation using evanescent waves and structured light. Fundamentally, the interplay between the IPM and polarization topology remains unexplored, significantly restricting its potential applications. Here, we observe the high-order polarization topological charges (PTCs) in the IPM and expand their capabilities in versatile particle manipulation. PTCs originate from spatial distributions of linear polarizations in vector beams. When the PTC equals 1, the IPM can be utilized to rotate particles. Distinctively, for higher-order PTCs, rotational potential-well arrays with controllable rotation directions emerge to trap and rotate various numbers of particles. This work uncovers a holistic and complete understanding of the IPM by investigating its link to the polarization distribution. It also suggests a credible way to harness polarization-topology optical forces, offering significant potential for biophysical and quantum applications.

Transistor-type optoelectronic sensors (OESs), which integrate transistor architectures with photodetection, have become an important platform for advancing optoelectronic sensing technologies. Their electrical tunability and structural versatility enable programmable mapping between optical inputs and electrical outputs, extending sensing capabilities beyond those of conventional two-terminal devices. These attributes position transistor-type OESs as promising candidates for in-sensor signal encoding and computing. Recent developments have shown a clear evolution from basic light intensity detection towards multifunctional perception, with advantages in edge extraction, machine vision and high-dimensional photodetection. This Review surveys the operating principles, device architectures and gate-tunable photoresponses that underpin this class of sensors. Progress at the interface of bioinspired design and intelligent algorithms is highlighted, illustrating how transistor-type OESs are being shaped into platforms that are capable of complex, adaptive functionality. The key challenges and opportunities that may guide the future development of transistor-type OESs are then outlined. Transistor-type optoelectronic sensors combine photodetection with gate-tunable transistor architectures, enabling programmable and multifunctional sensing beyond conventional devices. This Review outlines their operating principles and architectures, and highlights opportunities for intelligent, next-generation optoelectronic sensing.

Nonreciprocal thermal radiation offers a route to decouple spectral directional absorptivity and emissivity, thereby enabling new paradigms in thermal-photonic systems. However, in magneto-optical platforms, the intrinsic gyroelectric response generally confines observable nonreciprocity to transverse-magnetic (TM) polarization, while the transverse-electric (TE) response is absent. In this work, we experimentally demonstrate, for the first time, a local thermal metasurface strategy to activate TE-polarized nonreciprocity by creating artificial gyromagnetic response in a gyroelectric semiconductor platform. We further extend this mechanism to broadband dual-polarization operation employing a nonlocal thermal metasurface, which combines a resonator supercell with gradient-doped epsilon-near-zero magneto-optical multilayers. Pronounced absorptivity contrast is maintained over 22-27 μm for TE polarization and 19-27 μm for TM polarization. This platform provides a mechanism-based route to achieve broadband and dual-polarization nonreciprocal thermal absorption, opening new opportunities for advancing radiative energy-conversion devices.

Thermal rectification enables asymmetric heat flow and offers transformative potential for thermal management under extreme environments, yet its practical development has been constrained by a fundamental trade-off between high-temperature stability and nonlinear thermal response. Conventional rectifiers face intrinsic limitations, with operating temperatures below 900 kelvin and rectification ratios under 3.5. Here, we present a metaceramic, a monolithic metamaterial ceramic, architected with multiscale graded porosity that synergistically integrates four nonlinear heat transfer mechanisms: ion-tailored conduction, cavity-modulated radiation, chaotic advection-enhanced convection, and spontaneous convective dissipation. This metaceramic achieves a record thermal rectification ratio of 8.5 at 2473 kelvin, surpassing previous benchmarks by over 140%. In addition, the design's continuum-like, functionally partitionable nature enables its extension into a triaxial ultrahigh-temperature rectifier, which provides programmable, volumetric thermal flow control along three independent axes, effectively elevating rectification from a scalar to a tensor-like property. By decoupling and recombining multimodal nonlinearities within a single material, we overcome the classical stability-nonlinearity conflict. Our work establishes a metamaterials platform for breaking thermal reciprocity under extreme conditions, with implications for heat management in hypersonic systems, spacecraft, and energy technologies.

Valley photonics supports edge transport robust to sharp bends and disorder. However, conventional valley states, typically developed within a quantized valley Chern number framework, remain limited group velocity and bandwidth, restricting their applicability in high-speed, high-capacity on-chip transport. By relaxing the use of a sizable valley Chern number as the primary constraint in performance optimization, we leverage Dirac-mass engineering and electromagnetic mode control to simultaneously enhance the bandwidth and group velocity of valley transport. By combining extreme inversion-symmetry breaking with effective suppression of mode mixing, the platform restores an approximately scale-invariant interfacial mass profile, enabling both a maximized valley bandgap and a near-Dirac group velocity. Near-field measurements directly confirm unidirectional valley propagation with deep-subwavelength confinement and robustness against sharp bends. The system supports estimated error-free transmission at 2 Gbps and an open eye at symbol rates approaching the carrier frequency, with a carrier-normalized symbol rate exceeding those of previously reported valley photonic platforms by more than one order of magnitude. These findings establish a practical design route for high-performance valley photonics, offering ultrabroadband, high-velocity, and compact signal transport with potential applications in high-capacity photonic interconnect. The authors demonstrate ultrabroadband valley transport with near-Dirac group velocity through Dirac-mass engineering and mode control.

Spectral measurements provide fundamental insights into wave systems by revealing resonances, mode hybridization, and light-matter interactions. However, intrinsic dissipation and measurement-induced spectral broadening often conceal the underlying hybridized light-matter states that give rise to measured spectra. Here, we establish a space-time Fourier correspondence that interprets spectral broadening as an effective temporal attenuation, giving rise to a temporal Fourier optics framework for recovering hidden spectral information. Implemented through a temporal point-spread-function (TPSF) reconstruction method, the framework compensates the effective temporal decay before Fourier transformation, directly reconstructing intrinsic spectral responses from experimentally measured spectra without repeated frequency synthesis or model-dependent fitting. We experimentally validate the approach in deterministic single-molecule Au nanosphere dimers and open Au@Ag nanorod- and nanotriangle-based plasmonic nanocavities coupled to J-aggregate excitons. Across these diverse platforms, TPSF consistently reconstructs hidden upper and lower polaritonic branches, thereby revealing the underlying hybridized light-matter states and strong coupling that remain unresolved in conventional scattering spectra. The reconstructed spectra agree closely with the recently developed complex-frequency formalism while offering a considerably simpler and more experimentally accessible implementation. Beyond strong light-matter coupling, temporal Fourier optics establishes a general framework for uncovering physical states hidden by dissipation, opening new opportunities for spectroscopy, imaging, sensing, and inverse wave measurements across photonics and wave physics.

Conventional coherent light-field manipulation techniques inherently conflict with the spatiotemporal incoherence of thermal radiation sources. While recent advances in thermophotonics have facilitated directional thermal emission, arbitrary thermal wavefront control—a cornerstone for advanced functionalities like focusing and holography—remains an unaddressed challenge. Here, we report a generalized recipe of designing meta-emitters with lossy and lossless outer boundaries, that enables thermal emission with arbitrarily tailored wavefront. Lossy and lossless surfaces on two sides of the meta-emitter are synergistically coupled by a single-mode waveguide, transforming incoherent thermal photons to coherent surface waves for wavefront shaping functionalities. Designer surface mode of meta-emitter permits the independent optimization of photon lifetime and propagation length, thus enabling scalable spatial coherence engineering. For the proof of concept, we experimentally demonstrate near-diffraction-limited self-focusing emission, quasi-two-dimensional (quasi-2D) high-quality thermal holography without speckle noise and spatial-multiplexed holography. Coupling optimization further suggests that spatial coherence exceeding 1000λ0 are achievable. Our proposed meta-emitter establishes a paradigm-shifting framework to integrate stochastic thermodynamic emission with precision photonic engineering, opening avenues for information-rich thermal radiation technologies. Wavefront control is inherently incompatible with thermal incoherence in general. To address this challenge, the authors propose a meta-emitter architecture featuring two tailored grooves interconnected by a waveguide tunnel enabling the conversion of thermal photons into coherent surface waves, thereby experimentally demonstrating feasible thermal wavefront manipulation— including thermal self-focusing and holography.

Abstract Chiral metasurfaces leveraging bound states in the continuum (BICs) offer a powerful route for enhancing light–matter interactions. However, existing quasi-BIC architectures typically face a fundamental trade-off between high quality (Q) factors and wide-angle chiral operation. Most designs confine strong circular dichroism (CD) to isolated points in momentum space (k-space) and often rely on intricate three-dimensional (3D) meta-atoms, rendering them highly sensitive to fabrication imperfections and angular misalignment. Here, we experimentally realize a planar dielectric metasurface that supports a wide k-domain chirality arising from accidental BICs with a net zero-topological-charge (ZTC). By lifting a Dirac-type degeneracy through controlled in-plane and out-of-plane symmetry breaking, we induce a deterministic topological evolution in which the same-handed circularly polarized (C) points migrate toward and accumulate near the Γ point, while the opposite-handed singularities annihilate or shift to higher k-space. This mechanism delivers record-level performance—an ultrahigh Q-factor (~ 104), near-unity linear and nonlinear CD (0.99/0.999), and robust angular coverage (|k x P/2π, k y P/2π|< 0.06)—all within a fabrication-friendly, single-layer dielectric platform. These results establish a new regime for chiral photonics, unifying high chiral purity, angular robustness, and topological stability in a scalable planar architecture.

Pancharatnam-Berry (PB) metasurfaces encode the geometric phase through the rotation of the meta-atom, which exhibits opposite phases and nearly equal conversion amplitudes in the two cross-polarized channels. This spin duality has long restricted PB metasurfaces to spin-symmetric responses with insufficient contrast for spin-selective operation. Here we experimentally demonstrate a regime in which the geometric phase is preserved while its spin duality is deliberately broken. By engineering the pillar-lattice symmetry mismatch together with the etch depth to maximize contrast, we decouple the conversion amplitudes of the two spin channels without affecting the geometric-phase evolution. This enables a spin-asymmetric geometric-phase response that has not been accessible in conventional PB designs. We verify the broken duality through far-field measurements that reveal the selective suppression of the conjugate channel normally enforced by the PB phase. These results establish an accessible pathway to geometric-phase metasurfaces operating beyond their long-standing spin-duality constraint, enabling new forms of spin-dependent wavefront control in optical communications and displays with flat-optical elements.