posted on 2022-09-16, 14:33authored byLu Zhang, Kun Gao, Fanfan Lu, Lei Xu, Mohsen Rahmani, Lixun Sun, Feng Gao, Wending Zhang, Ting Mei
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
(Sb2S3), 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 Sb2S3 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.