Song Gao

Flexible sensing technology based on hydrogel‐based smart gloves enables accurate gesture recognition in complex environments, but such gloves degrade in dry, high‐temperature, and underwater conditions, and their complex assembly limits practical usability. Here, a smart glove monitoring system is developed by integrating a poly(benzyl methacrylate‐co‐2‐hydroxyethyl acrylate)/ionic liquid (P(BZMA‐co‐HEA)/IL) ionogel sensing layer with a flexible printed circuit board (FPCB). The ionogel is constructed through a network‐constrained ionic soft‐space regulation strategy, where HEA‐rich segments strengthen the network, IL provides deformation‐adaptive ionic soft spaces, and BZMA‐rich hydrophobic segments suppress water penetration. The optimized ionogel combines stretchability (up to 1100%), weight retention (98.86% at room temperature and 95.25% at 65°C), favorable adhesion, anti‐swelling behavior, and stable sensing performance under multiple environmental conditions. The FPCB enables a detachable and reconfigurable sensor array, ensuring stable interfacial contact and wearing flexibility. By further combining multi‐channel signal acquisition, fully connected neural network (FCNN)‐assisted gesture classification, and real‐time alert feedback, the smart glove functions as an integrated sensing‐recognition‐warning platform, achieving 99.92% gesture recognition accuracy and enabling reliable underwater communication and safety warning. This work establishes an effective material design and integration strategy for environmentally adaptive smart gloves.

Passive radiative cooling is a promising thermal management technology that requires no external energy to achieve cooling. By emitting thermal radiation through the atmospheric transparency window to the cold outer space, it can maintain a temperature below the ambient environment. In this work, a broadband selective-emissivity emitter for daytime radiative cooling is proposed. The presented emitter achieves strong solar reflectivity and enhanced thermal emissivity within the atmospheric window. Simulation findings demonstrate that the proposed thin-film structure possesses excellent reflective performance from 0.3 μ m to 2.5 μ m, achieving an average reflectivity of 0.98. Meanwhile, an average emissivity of 0.93 is obtained from 8 μ m to 13 μ m, enabling efficient thermal radiation to outer space. Owing to its broadband selective-emission characteristics, the emitter effectively enhances the spectral matching between thermal radiation and the atmospheric window. Based on thermal equilibrium equations, the net cooling heat flux of the emitter is determined to be 117.64 W m ⁻² under typical daytime conditions. Compared with conventional broadband emitters, the proposed structure concentrates thermal emission predominantly during the atmospheric window, exhibiting excellent broadband selective-emission characteristics. The proposed design also shows promising potential for energy-efficient buildings, electronic heat dissipation, and temperature regulation of photovoltaic systems.

Optical metasurfaces offer significant advantages for nanoscale light manipulation, enabling advanced high‐resolution optical displays such as near‐field nanoprinting and far‐field holography. However, integrating continuous grayscale nanoprinting with vectorial holography simultaneously has remained a challenge. Here, we propose a novel strategy to achieve this crucial multifunctionalities by developing a visible‐band dielectric diatomic metasurface, whose unit cell is ingeniously designed to comprise multiple silicon nanopillars functioning as nanostructured half‐wave and quarter‐wave plates. Through engineered phase relationships, these nanopillars can collectively cooperate to convert arbitrary incident polarization states into linearly polarized light, with the polarization angle precisely controlled by nanopillar rotation. More importantly, without altering the polarization state, the transmitted light phase is further tailored by introducing a propagation phase via careful geometric design of the nanopillars. This independent and complete control over both arbitrary‐to‐linear polarization conversion and transmission phase allows our diatomic metasurface to concurrently realize versatile optical displays in both near and far fields. To verify its multifunctional light manipulation ability, several metasurface samples were fabricated and characterized, successfully demonstrating continuous or multi‐level grayscale nanoprinting alongside vectorial holography. We anticipate that the proposed strategy will offer new perspectives for metasurface‐based multifunctional optical display and integration.

Benefiting from their exceptional capability for manipulation of versatile light properties, metasurfaces have emerged as a promising platform for optical encryption. However, existing metasurface‐based encryption schemes are often constrained by limited concealment and a lack of post‐fabrication reconfigurability. Here, we propose a reconfigurable steganographic strategy that integrates metasurface‐enabled optical encryption with hidden cryptographic algorithms. In this scheme, chaotic encryption and steganographic algorithms are jointly employed to embed cryptographic ciphertexts and keys into four optically encoded meta‐images in a highly concealed manner. A single‐layer silicon metasurface independently encodes these meta‐images across multiple optical dimensions, including wavelength, polarization, and spatial distance (near‐ and far‐field), under white‐light and monochromatic illumination. Most importantly, the ciphertexts and keys as well as the choice of encryption algorithm are decoupled from the metasurface and can be flexibly updated via network control, enabling reconfigurable encryption without modifying the metasurface. Experiments confirm that secret images can only be recovered through the cooperative implementation of optical and algorithmic decryption. Our work has improved the security, concealment, and reconfigurability of metasurface‐based optical encryption, offering new opportunities for dynamic and interactive information‐security applications.

Multifunctional manipulation of optical fields with multiple degrees of freedom is essential for integrated photonic systems, yet achieving coordinated and independent control of polarization and phase remains challenging. Here, we propose a polarization-tunable multifocal metalens enabled by a bilayer metasurface with integrated polarization rotation. By introducing the interlayer rotation angle difference as an additional degree of freedom, a rigorous theoretical framework is established, revealing that the transmitted polarization undergoes a deterministic rotation equal to twice the interlayer rotation difference while preserving its ellipticity. Under circularly polarized incidence, the polarization state remains unchanged, with only geometric phase modulation induced. This mechanism enables a continuous and predictable mapping between input and output polarization states. By further incorporating an independent propagation phase via selected nanopillars, polarization and phase can be engineered independently within a unified framework. Based on this strategy, a polarization-tunable multifocal metalens is numerically demonstrated, generating multiple focal spots with distinct and switchable polarization states at predefined positions. The polarization state at each focus can be tuned solely by varying the incident polarization angle, without modifying the device structure. This work provides a versatile and physically intuitive strategy for multifunctional metasurface design and integrated photonic applications.

Metasurfaces provide a powerful platform for high-resolution multichannel optical displays, and the conditional image reconstruction based on light wavelength and polarization further renders it highly promising for optical encryption. However, material dispersion causes these functionalities to persist at off-design wavelengths, leading to unintended image leakage or crosstalk. To address these issues, a metasurface-on–Fabry–Perot cavity (MoFP) platform is proposed and demonstrated. Unlike a standalone metasurface lacking pronounced resonant features, the MoFP enables spectrally filtered dual-narrowband transmission while simultaneously providing independent amplitude and polarization control at two bands centered at 800 and 1200 nm, respectively. A 3-bit intensity encoding is established and utilized to demonstrate a three-channel metasurface encrypted display. Simulation results show that a binary image is observed under circularly polarized illumination at 800 nm, while switching the wavelength to 1200 nm and placing an analyzer orientated at 0° and 45° gives rise to two different binary images. Most importantly, compared with a standalone metasurface, the MoFP can safely secure these images within a much narrower wavelength band with minimal crosstalk. We anticipate the proposed platform can give new insight to optical metasurface encryption.

Flexible tactile sensors are rapidly evolving toward high‐resolution, multimodal sensing and large‐area integrability, but traditional manufacturing processes face inherent limitations in complex 3D structure construction, material system compatibility, and fast and efficient manufacturing. Additive manufacturing (AM) technology, with its unique advantages such as on‐demand forming, high structural freedom, and multi‐material collaborative processing, is becoming a core driving force for breakthroughs in sensing performance and integration, moving the field toward cross‐process integration and accelerated innovation. However, AM processes and applications have not yet formed a complete system, and the development and intelligentization of AM‐based flexible tactile sensors have reached a bottleneck, urgently requiring a comprehensive and systematic review to achieve breakthrough progress. Therefore, this review systematically examines the mechanisms by which different AM processes affect the material properties, structural construction, and overall performance of devices, evaluates their applicability, process advantages, and limitations in micro‐nano structure manufacturing, and summarizes their latest advancements in intelligent systems and emerging application scenarios. Finally, it provides an in‐depth outlook on the future development challenges and potential opportunities of AM‐based flexible tactile sensors.

In this paper, a terahertz temperature-controlled switch (TCS) composed of VO ₂ and Cu is proposed. The dual-state bandwidth and amplitude perform excellently, an overlapping bandwidth of 79%, and a modulation depth of over 90%.

Secret‐sharing metasurfaces provide a new platform for the transmission of distributed cryptographic images, greatly enhancing the security of optical encryption. In view of the situation in practical applications where keys are prone to loss or tampering, a novel secret sharing encryption scheme enabled by the metasurface technology is proposed. Shamir's secret sharing strategy is first utilized to divide the secret information into four shares, providing the first layer of algorithmic encryption. These secret shares are further embedded into four distinct QR code images, which are physically implemented via a metasurface platform, achieving a second layer of hardware‐level encryption. The scheme is numerically validated using a bilayer silicon metasurface designed with bidirectional asymmetric circular‐to‐linear polarization conversion capability, enabling nanostructure orientation angle decoupled 4‐bit intensity encoding to ensure secure access to the four binary images under different illumination directions and polarization states. Based on the shares extracted from the four QR code images, the secret information is successfully reconstructed via the Lagrange interpolation. The demonstrated method combines optical encryption with polynomial calculation, enhancing both digital and physical security, and shows strong potential applications in data storage, optical display, and distributed secure communication.