Key Laboratory of Light Field Manipulation and Information Acquisition, Ministry of Industry and Information Technology, Northwestern Polytechnical University, Xi'an 710129, China.
Advanced Optics & Photonics Laboratory, Nottingham Trent University, Nottingham NG11 8NS, United Kingdom.
Nano Lett. 2022 Sep 28;22(18):7628-7635. doi: 10.1021/acs.nanolett.2c02739. Epub 2022 Sep 16.
Low-cost large-area chirality meta-devices (CMDs) with adjustable optical chirality are of great interest for polarization-sensitive imaging, stereoscopic display, enantioselectivity analysis, and catalysis. Currently, CMDs with adjusted chiroptical responses in the mid-infrared to terahertz band have been demonstrated by exploiting photocarriers of silicon, pressure, and phase-change of GSTs but are still absent in the visible band, which in turn limits the development of chiral nanophotonic devices. Herein, by employing a phase-change material (SbS), we present a protocol for the fabrication of wafer-scale visible-band enantiomeric CMDs with handedness, spectral, and polarization adjustability. As measured by circular dichroism, the chirality signs of CMDs enantiomers can be adjusted with SbS from amorphous to crystalline, and the chirality resonance wavelength can also be adjusted. Our results suggest a new type of meta-devices with adjustable chiroptical responses that may potentially enable a wide range of chirality nanophotonic applications including highly sensitive sensing and surface-enhanced nanospectroscopy.
低成本大面积手性超构器件（CMD）具有可调谐的光学手性，在偏振敏感成像、立体显示、对映选择性分析和催化等领域具有重要应用。目前，通过利用硅的光生载流子、压力和 GST 的相变化已经实现了中红外到太赫兹波段可调谐的手性响应的 CMD，但在可见光波段仍不存在，这反过来又限制了手性纳米光子器件的发展。在此，我们采用相变材料（SbS），提出了一种用于制造具有手性、光谱和偏振可调性的晶圆级可见光波段对映手性 CMD 的方案。通过圆二色性测量，CMD 对映体的手性符号可以通过 SbS 从非晶态调整到晶态，并且手性共振波长也可以调整。我们的研究结果表明，一种具有可调谐手性响应的新型超构器件，可能为包括高灵敏度传感和表面增强纳米光谱学在内的各种手性纳米光子学应用提供了新的可能性。
