Electrically reconfigurable non-volatile metasurface using low-loss optical phase-change material
Abstract
Active metasurfaces promise reconfigurable optics with drastically improved compactness, ruggedness, manufacturability and functionality compared to their traditional bulk counterparts. Optical phase-change materials (PCMs) offer an appealing material solution for active metasurface devices with their large index contrast and non-volatile switching characteristics. Here we report a large-scale, electrically reconfigurable non-volatile metasurface platform based on optical PCMs. The optical PCM alloy used in the devices, Ge2Sb2Se4Te (GSST), uniquely combines giant non-volatile index modulation capability, broadband low optical loss and a large reversible switching volume, enabling notably enhanced light-matter interactions within the active optical PCM medium. Capitalizing on these favourable attributes, we demonstrated quasi-continuously tuneable active metasurfaces with record half-octave spectral tuning range and large optical contrast of over 400%. We further prototyped a polarization-insensitive phase-gradient metasurface to realize dynamic optical beam steering.
- Publication:
-
Nature Nanotechnology
- Pub Date:
- June 2021
- DOI:
- 10.1038/s41565-021-00881-9
- arXiv:
- arXiv:2008.06659
- Bibcode:
- 2021NatNa..16..661Z
- Keywords:
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- Physics - Applied Physics;
- Physics - Optics
- E-Print:
- 12 pages, 5 figures