Liquid crystal-based image holography with broadband response and polarization insensitivity.

We propose and experimentally demonstrate liquid crystal-based computer-generated image holography enabled by the Pancharatnam-Berry phase modulation. Such a device exhibits distinctive properties, such as natural light illumination, polarization insensitivity, broadband optical response, high polarization conversion efficiency, and direct visibility to the naked eye. These unique attributes make this type of image holography a promising avenue for applications in optical information storage, anti-counterfeiting, and advanced information displays.

Structural-color meta-nanoprinting embedding multi-domain spatial light field information.

Recently, multifunctional metasurface has showcased its powerful functionality to integrate nanoprinting and holography, and display ultracompact meta-images in near- and far-field simultaneously. Herein, we propose a tri-channel metasurface which can further extend the meta-imaging ranges, with three independent images located at the interface, Fresnel and Fourier domains, respectively. Specifically, a structural-color nanoprinting image is decoded right at the interface of the metasurface, enabled by varying the dimensions of nanostructures; a Fresnel holographic image and another Fourier holographic image are present at the Fresnel and Fourier (far-field) domains, respectively, enabled by geometric phase.

Bidirectional high-speed optical wireless communication with tunable large field of view assisted by liquid crystal metadevice.

Beam-steered infrared (IR) light communication has gained tremendous attention as one of the solutions of congested wireless communication traffic. High performance active beam-steering devices play a crucial role in data allocation and exchange. Conventional beam-steering devices such as spatial light modulator (SLM) and micro-electrical mechanical system (MEMS) mirror and the current emerging nonmechanical beam-steering metasurface-based devices are challenging to realize a large tunable steering angle beyond several degrees, which significantly hinders the spatial application of optical wireless communications (OWC).

Experimental retrieval of metaholographic images via evanescent wave using a single-layer nanostructure for encryption.

Metasurfaces have demonstrated significant potential in optical encryption and anti-counterfeiting due to their incredible capability of manipulating various light properties. However, previous metasurface-encryption methods did not sufficiently explore the spatial frequency aspect, particularly regarding evanescent waves. Here, we propose an encryption scheme by introducing evanescent waves into the encoding and decoding processes.

Tri-channel metasurface fusion of continuously varying gray levels for nanoprinting and holographic displays.

Metasurfaces are extensively utilized in nanoprinting and hologram fusion displays due to their superior wavefront shaping capabilities. However, the creation of continuously varying grayscale images based on conventional Malus's law necessitates the use of at least one polarizer for observation, which compromises the metasurface's integration. In this study, inspired by the Jacobi-Anger expansion, we propose a tri-channel metasurface to establish three independent information channels for simultaneous grayscale nanoprinting and polarization multiplexed holography.

Upper limit on the polarization-assisted amplitude modulation capability of cascaded single-cell wave-plate-like metasurfaces.

The Jones matrix method offers a robust framework for designing polarization multiplexed metasurfaces (PMMs). Traditional PMMs design involves initially defining functions and working channels, then mapping feature functions to adjustable parameters of metasurfaces. However, this approach makes it difficult to predict how working channels affect metasurface features.

Minimalist design of multifunctional metasurfaces for helicity multiplexed holography and nanoprinting.

Recently, polarization multiplexing has become a common strategy to enhance the information capacity of metasurfaces. Nevertheless, the intricate design of anisotropic nanostructures forming a polarization multiplexed metasurface poses a significant challenge, increasing the requirements for manufacturing processes and diminishing overall robustness. Herein, we present a minimalist metasurface comprised of only two kinds of nanostructures to achieve the integration of continuous-amplitude modulated nanoprinting and eight-step phase-only helicity-multiplexed holography.

Metasurface-enabled 3D imaging via local bright spot gray scale matching using the structured light dot array.

Three-dimensional (3D) imaging is widely utilized in various applications, such as light detection, autonomous vehicles, and machine vision. However, conventional 3D imaging systems often rely on bulky optical components. Metasurfaces, as next-generation optical devices, possess flexible wavefront modulation capabilities and excellent combination with computer vision algorithms.

Electrically tunable planar liquid-crystal singlets for simultaneous spectrometry and imaging.

Conventional hyperspectral cameras cascade lenses and spectrometers to acquire the spectral datacube, which forms the fundamental framework for hyperspectral imaging. However, this cascading framework involves tradeoffs among spectral and imaging performances when the system is driven toward miniaturization. Here, we propose a spectral singlet lens that unifies optical imaging and computational spectrometry functions, enabling the creation of minimalist, miniaturized and high-performance hyperspectral cameras.

hUCMSC-derived exosomes protect against GVHD-induced endoplasmic reticulum stress in CD4 T cells by targeting the miR-16-5p/ATF6/CHOP axis.

Exosomes generated from mesenchymal stem cells (MSCs) are thought to be a unique therapeutic strategy for several autoimmune deficiency illnesses. The purpose of this study was to elucidate the protective effects of human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exo) on CD4 T cells dysfunction during graft-versus-host disease (GVHD) and to identify the underlying processes involved. Here, we showed that hUCMSC-Exo treatment can effectively attenuate GVHD injury by alleviating redox metabolism disorders and inflammatory cytokine bursts in CD4 T cells.

Switchable Two-Dimensional AND and Exclusive OR Operation Based on Dual-Wavelength Metasurfaces.

Logic operation serves as the foundation and core element of computing networks; it will bring huge vitality to advanced information processing with its adaptation in the optical domain. As fundamental logic operations, AND and exclusive OR (XOR) operations serve a multitude of purposes, such as their ability to cooperate in enabling image processing and interpretation. Here, we propose and experimentally demonstrate a wavelength multiplexed AND and XOR function based on metasurfaces.

Perovskite single-pixel detector for dual-color metasurface imaging recognition in complex environment.

Highly efficient multi-dimensional data storage and extraction are two primary ends for the design and fabrication of emerging optical materials. Although metasurfaces show great potential in information storage due to their modulation for different degrees of freedom of light, a compact and efficient detector for relevant multi-dimensional data retrieval is still a challenge, especially in complex environments. Here, we demonstrate a multi-dimensional image storage and retrieval process by using a dual-color metasurface and a double-layer integrated perovskite single-pixel detector (DIP-SPD).

Beam-steering metasurfaces assisted coherent optical wireless multichannel communication system.

The metasurface based beam-steering devices with the advantages of large steering angles, arbitrary channels and ultra-compactness have played an important role for data allocation and exchange in the optical wireless communication. However, the current metasurface based optical wireless communication systems are mainly on intensity modulation and direct detection (IM/DD), which shows a relative lower transmission capacity, lower received optical signal-to-noise ratio (OSNR) and complexity of system. In this study, a bidirectional multichannel optical wireless system enabled by a polarization independent metasurface with coherent modulation and reception is designed and experimentally demonstrated, which exhibits exclusive 100 Gbps coherent optical signals to multiusers with their own wavelengths, 2 m free space distance and field of view of 20° × 20°.

All-Optical Multiplexed Meta-Differentiator for Tri-Mode Surface Morphology Observation.

Current optical differentiators are generally limited to realizing a single differential function once fabricated. Herein, a minimalist strategy in designing multiplexed differentiators (1 - and 2 -order differentiations), implemented with a Malus metasurface consisting of single-sized nanostructures is proposed, thus improving the functionality of optical computing devices without the cost of complex design and nanofabrication. It is found that the proposed meta-differentiator exhibits excellent differential-computation performance and can be used for simultaneous outline detection and edge positioning of objects, corresponding to the functions of the 1 - and 2 -order differentiations respectively.

Phase-assisted Bessel-metasurface: a single-sized approach for simultaneous printing and holography.

Due to the unprecedented wavefront shaping capability, the metasurface has demonstrated state-of-the-art performances in various applications, especially in printing and holography. Recently, these two functions have been combined into a single metasurface chip to achieve a capability expansion. Despite the progress, current dual-mode metasurfaces are realized at the expense of an increase in the difficulty of the fabrication, reduction of the pixel resolution, or strict limitation in the illumination conditions.

Tiger Amulet inspired high-security holographic encryption via liquid crystals.

Due to the precise and continuous regulation of phase, holographic encryption based on metasurfaces and liquid crystals (LCs) has been proposed to encrypt the information by manipulating the wavelength, polarization, etc. However, the security cannot be fully guaranteed since the requirements of decoding methods for these schemes are generally not very strict and vulnerable for exhaustive attack. Furthermore, any part of the hologram stolen may lead to the disclosure of the hidden information regardless of the generation mode of phase delay or the selection of media material, so the security needs to be further improved.

Phase-assisted angular-multiplexing nanoprinting based on the Jacobi-Anger expansion.

Featuring with ultracompactness and subwavelength resolution, metasurface-assisted nanoprinting has been widely researched as an optical device for image display. It also provides a platform for information multiplexing, and a series of multiplexed works based on incident polarizations, operating wavelengths and observation angles have emerged. However, the angular-multiplexing nanoprinting is realized at the cost of image resolution reduction or the increase of fabrication difficulty, hindering its practical applications.

Protective effect of hydroxysafflor yellow A on renal ischemia‑-reperfusion injury by targeting the Akt‑Nrf2 axis in mice.

Ischemic/reperfusion (I/R) injury is the primary cause of acute kidney injury (AKI). Hydroxysafflor yellow A (HSYA), a natural compound isolated from , has been found to possess anti-inflammatory and antioxidant properties. However, the protective effects and potential mechanism of HSYA on I/R-induced AKI remains unclear.

Tri-channel metasurface for watermarked structural-color nanoprinting and holographic imaging.

Structural-color nanoprinting, which can generate vivid colors with spatial resolution at subwavelength level, possesses potential market in optical anticounterfeiting and information encryption. Herein, we propose an ultracompact metasurface with a single-cell design strategy to establish three independent information channels for simultaneous watermarked structural-color nanoprinting and holographic imaging. Dual-channel spectrum manipulation and single-channel phase manipulation are combined together by elaborately introducing the orientation degeneracy into the design of variable dielectric nanobricks.

Dual-channel anticounterfeiting color-nanoprinting with a single-size nanostructured metasurface.

Metasurface-based structural-colors are usually implemented by changing the dimensions of nanostructures to produce different spectral responses. Therefore, a single-size nanostructured metasurface usually cannot display structural-colors since it has only one design degree of freedom (DOF), i.e.

Multifold Integration of Printed and Holographic Meta-Image Displays Enabled by Dual-Degeneracy.

By virtue of the unprecedented ability of manipulating the optical parameters, metasurfaces open up a new avenue for realizing ultra-compact image displays, e.g., nanoprinting on the surface and holographic displaying in the far-field.

Metasurface-enabled three-in-one nanoprints by multifunctional manipulations of light.

In metasurface-based ultra-compact image display, color-nanoprints, gray-imaging elements, and binary-pattern-imaging elements are three different types of nanoprints, implemented with different mechanisms of light manipulation. Here, we show the three functional elements can be integrated together to form a "three-in-one" nanoprint with negligible crosstalk, merely with a single-cell nanostructured design approach. Specifically, by decoupling spectrum and polarization-assisted intensity manipulations of incident light, the proposed metasurface appears as a dual-color nanoprint under a broadband unpolarized light source illumination, while simultaneously displaying an independent continuous gray image and another binary-pattern in an orthogonal-polarization optical setup with different polarization controls.

Mass-Manufactured Beam-Steering Metasurfaces for High-Speed Full-Duplex Optical Wireless-Broadcasting Communications.

Beam-steering devices, which are at the heart of optical wireless-broadcasting communication links, play an important role in data allocation and exchange. An ideal beam-steering device features large steering angles, arbitrary channel numbers, reconfigurability, and ultracompactness. However, these criteria have been achieved only partially with conventional beam-steering devices based on waveguides, micro-electricalmechanical systems, spatial light modulators, and gratings, which will substantially limit the application of optical wireless-broadcasting communication techniques.

Metasurfaces with single-sized antennas for reconstructing full-color holographic images without cross talk.

Designing a color hologram with conventional metasurfaces usually resorts to a supercell strategy or single-sized approach with different incident angles. However, these designs still have their own drawbacks that need to be further solved. Herein, we show a new, to the best of our knowledge, single-sized strategy to design full-color geometric meta-holograms by utilizing the conjugation property of two circularly polarized lights with opposite handedness and diffraction dispersion.