Reconfigurable Ultraviolet and High-Energy Visible Dielectric Metamaterials
Reconfigurable Ultraviolet and High-Energy Visible Dielectric Metamaterials
复制标题
DOI：
10.1021/acs.nanolett.8b04576
复制
发表时间：
2019-03-01
期刊：
影响因子：
10.8
通讯作者：
Zheludev, Nikolay, I
中科院分区：
文献类型：
--
作者：
Gholipour, Behrad;Piccinotti, Davide;Zheludev, Nikolay, I
具有可调谐和可切换的紫外（UV）到高能可见光（HEV）光学特性的光子材料可能有利于传感、高密度光学存储器、光束控制、自适应光学和光调制等应用。在这里，我们首次展示了在 UV-HEV 光谱范围内工作的非易失性可切换介电超材料。低损耗 ZnS/SiO2 层状复合材料中的纳米光栅超材料和硫族化物相变介质碲化锗锑（Ge2Sb2Te5 或 GST）在 UV-HEV 波长下表现出反射共振，该反射共振基本上被硫族化物层中光诱导（非晶-结晶）相变所改变。尽管存在有损 GST，但 ZnS/SiO2 在 UV-HEV 光谱范围内的透明度（低损耗）确保了高达 Q 的谐振品质因数（接近 15），并且 Q 值在结晶时随着 Ge2Sb2Te5 折射率的降低而增加。然而值得注意的是，这种切换使共振光谱位置保持不变。
Photonic materials with tunable and switchable ultraviolet (UV) to high-energy visible (HEV) optical properties may benefit applications such as sensing, high-density optical memory, beam-steering, adaptive optics, and light modulation. Here, for the first time we demonstrate a nonvolatile switchable dielectric metamaterial operating in the UV-HEV spectral range. Nanograting metamaterials in a layered composite of low-loss ZnS/SiO, and the chalcogenide phase-change medium germanium-antimony-telluride (Ge2Sb2Te5 or GST) exhibit reflection resonances at UV-HEV wavelengths that are substantially modified by light-induced (amorphous-crystalline) phase transitions in the chalcogenide layer. Despite the presence of the lossy GST, resonance quality factors up to Q similar to 15 are ensured by the transparency (low losses) of ZnS/SiO2 in the UV-HEV spectral range and values of Q increase as the refractive index of Ge2Sb2Te5 decreases, upon crystallization. Notably, however, this switching leaves resonance spectral positions unchanged.