摘要：Metasurfaces provide a potent platform for the dynamic manipulation of electromagnetic ***⁃pled with phase-change materials,they facilitate the creation of versatile metadevices,showcasing various tun⁃able functions based on the transition between amorphous and crystalline ***,the inherent limitation in tunable states imposes constraints on the multiplexing channels of ***,this paper introduces a novel approach-a multi-functional metadevice achieved through the two-level control of the encoding phasechange *** the phase-change material Ge_(2)Sb_(2)Se_(4)Te1(GSST)and high refractive-index liquid di⁃iodomethane(CH_(2)I_(2)),this paper showcases precise control over electromagnetic wave *** GSST state governs the tunable function,switching it ON and OFF,while the presence of liquid in the hole dictates the deflection angle when the tunable function is ***,our tunable coding metasurface exhibits robust performance across a broad wavelength *** incorporation of high refractive-index liquid extends the regulatory dimension of the metadevice,enabling dynamic switching of encoding bit *** two-level tun⁃able metadevice,rooted in phase-change materials,presents a promising avenue for the dynamic control of func⁃tions.

摘要：人工微结构超表面近年来在偏振调控与色散调控领域都取得了诸多进展,然而传统方法计算超表面结构对椭圆偏振态的调控效果需要对每一个数据求解方程,因此实现任意偏振的消色差调控依然在复杂度上是一个挑战。一种基于坐标变换的正向计算方法用以快速计算超表面单元对任意偏振态的调控效果被提出,利用纯硅体系下的椭圆柱结构作为调控单元设计了工作在中红外波段的对椭圆偏振态调控的消色差聚焦超表面透镜。结果表明,此种方法与设计在极大简化计算流程的情况下,能够有效实现对椭圆偏振态的操控。相比于之前所报道的基于圆偏振或无偏振依赖的设计,该方法进一步拓展了超表面色散调控的应用范围,具有广阔的应用前景。