随着红外探测技术手段的多样化发展，红外隐身技术的需求日益迫切。由于传统的红外隐身技术面临着多途径目标探测和多功能兼容的严峻挑战，因此研究光学微纳结构红外隐身技术有着十分重要的意义。基于局域共振机制的亚波长尺度的光学微纳结构，极大地丰富了人们对光的传输行为的调控。在红外隐身技术领域，光学微纳结构可以针对红外辐射特性进行材料和结构的精细化设计，从而满足理想红外隐身发射光谱的需求，为发展更加多光谱、多功能、自适应的红外隐身技术提供全新的解决方案。文中围绕红外隐身技术的相关研究，首先介绍了多层薄膜吸收体、金属表面等离子激元、基于相变材料薄膜可调吸收体、智能化设计光学微纳结构实现光谱响应的基本原理，在此基础上，重点回顾了近年来基于光学微纳结构的红外隐身技术新特点，包括多光谱红外隐身技术、多功能红外隐身技术、自适应红外隐身技术的发展现状。最后，梳理了光学微纳结构红外隐身技术所存在的不足及面临的困难并对未来的研究方向和发展趋势进行了展望。

Metasurfaces have emerged as a flexible platform for shaping the electromagnetic field via the tailoring phase, amplitude, and polarization at will. However, the chromatic aberration inherited from building blocks’ diffractive nature plagues them when used in many practical applications. Current solutions for eliminating chromatic aberration usually rely on searching through many meta-atoms to seek designs that satisfy both phase and phase dispersion preconditions, inevitably leading to intensive design efforts. Moreover, most schemes are commonly valid for incidence with a specific spin state. Here, inspired by the Rayleigh criterion for spot resolution, we present a design principle for broadband achromatic and polarization-insensitive metalenses using two sets of anisotropic nanofins based on phase change material Ge₂Sb₂Se₄Te₁. By limiting the rotation angles of all nanofins to either 0 deg or 90 deg, the metalens with a suitable numerical aperture constructed by this fashion allows for achromatic and polarization-insensitive performance across the wavelength range of 4–5 μm, while maintaining high focusing efficiency and diffraction-limited performance. We also demonstrate the versatility of our approach by successfully implementing the generation of broadband achromatic and polarization-insensitive focusing optical vortex. This work represents a major advance in achromatic metalenses and may find more applications in compact and chip-scale devices.

Optical neural networks (ONNs), enabling low latency and high parallel data processing without electromagnetic interference, have become a viable player for fast and energy-efficient processing and calculation to meet the increasing demand for hash rate. Photonic memories employing nonvolatile phase-change materials could achieve zero static power consumption, low thermal cross talk, large-scale, and high-energy-efficient photonic neural networks. Nevertheless, the switching speed and dynamic energy consumption of phase-change material-based photonic memories make them inapplicable for in situ training. Here, by integrating a patch of phase change thin film with a PIN-diode-embedded microring resonator, a bifunctional photonic memory enabling both 5-bit storage and nanoseconds volatile modulation was demonstrated. For the first time, a concept is presented for electrically programmable phase-change material-driven photonic memory integrated with nanosecond modulation to allow fast in situ training and zero static power consumption data processing in ONNs. ONNs with an optical convolution kernel constructed by our photonic memory theoretically achieved an accuracy of predictions higher than 95% when tested by the MNIST handwritten digit database. This provides a feasible solution to constructing large-scale nonvolatile ONNs with high-speed in situ training capability.

超表面是一种基于亚波长各向异性单元结构的超薄平面光学器件，能够在微观尺度下调制电磁波相位、偏振和振幅等，从而实现波前的任意调控。超构透镜作为超表面走向实用化的重要代表，凭借其超强的光波操控能力、超紧凑结构、多功能性及与半导体工艺兼容等突出优点，引起了研究学者的极大兴趣。然而，已报道的超构透镜受限于相位分布设计，难以同时实现偏振复用及强度可调谐聚焦功能；且结构一旦确定，其电磁性能就被锁定，在灵活调制电磁波方面受到很大限制。为此，文中从各向异性单元结构的设计和优化入手，协同PB相位和传输相位，设计了两种能够在不同空间取向（横向和纵向）上实现自旋分裂的Ge₂Sb₂Se₄Te₁ (GSST) 相变超构透镜。通过改变入射圆偏振光的椭偏度，两超构透镜均可实现强度可调谐聚焦性能；通过调控相变材料Ge₂Sb₂Se₄Te₁从非晶态逐渐转变为结晶态，两超构透镜均可实现聚焦性能的连续调谐并最终达到“ON”和“OFF”的动态切换。所设计的自旋依赖强度可调谐相变超构透镜有望在多成像系统、机器视觉和显微成像等领域发挥重要作用。

Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission (EOT) in the terahertz (THz) region, whereby a giant forward light propagation can be created using constructive interference of tunneling surface plasmonic waves. However, numerous applications of THz meta-devices demand an active manipulation of the THz beam in free space. Although some studies have been carried out to control the EOT for the THz region, few of these are based upon electrical modulation of the EOT phenomenon, and novel strategies are required for actively and dynamically reconfigurable EOT meta-devices. In this work, we experimentally present that the EOT resonance can be coupled to optically reconfigurable chalcogenide metamaterials which offers a reversible all-optical control of the THz light. A modulation efficiency of 88% in transmission at 0.85 THz is experimentally observed using the EOT metamaterials, which is composed of a gold (Au) circular aperture array sitting on a non-volatile chalcogenide phase change material (Ge₂Sb₂Te₅) film. This comes up with a robust and ultrafast reconfigurable EOT over 20 times of switching, excited by a nanosecond pulsed laser. The measured data have a good agreement with finite-element-method numerical simulation. This work promises THz modulators with significant on/off ratios and fast speeds.Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission (EOT) in the terahertz (THz) region, whereby a giant forward light propagation can be created using constructive interference of tunneling surface plasmonic waves. However, numerous applications of THz meta-devices demand an active manipulation of the THz beam in free space. Although some studies have been carried out to control the EOT for the THz region, few of these are based upon electrical modulation of the EOT phenomenon, and novel strategies are required for actively and dynamically reconfigurable EOT meta-devices. In this work, we experimentally present that the EOT resonance can be coupled to optically reconfigurable chalcogenide metamaterials which offers a reversible all-optical control of the THz light. A modulation efficiency of 88% in transmission at 0.85 THz is experimentally observed using the EOT metamaterials, which is composed of a gold (Au) circular aperture array sitting on a non-volatile chalcogenide phase change material (Ge₂Sb₂Te₅) film. This comes up with a robust and ultrafast reconfigurable EOT over 20 times of switching, excited by a nanosecond pulsed laser. The measured data have a good agreement with finite-element-method numerical simulation. This work promises THz modulators with significant on/off ratios and fast speeds.

硫系玻璃具有超宽的红外透过光谱范围、较高的线性折射率、极高的光学非线性和超快的非线性响应，近年来在集成光子器件研究领域备受关注。首先回顾了硫系玻璃集成光波导的制备，综述了硫系集成光子器件在红外传感和高性能非线性应用方面取得的进展，然后介绍了硫系相变光子器件在光开关、光存储和光计算等方面的前沿进展，最后对目前硫系玻璃光子器件研究存在的问题进行了归纳，并对未来的研究方向进行了展望。