Journal
NANO LETTERS
Volume 18, Issue 5, Pages 2957-2963Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.nanolett.8b00351
Keywords
Tunable metasurface; transparent conducting oxide; beam steering; active nanophotonics; epsilon-near-zero materials; field effect modulation
Categories
Funding
- Samsung Electronics
- Air Force Office of Scientific Research [FA9550-16-1-0019]
Ask authors/readers for more resources
Active metasurfaces composed of electrically reconfigurable nanoscale subwavelength antenna arrays can enable real-time control of scattered light amplitude and phase. Achievement of widely tunable phase and amplitude in chip-based active metasurfaces operating at or near 1550 nm wavelength has considerable potential for active beam steering, dynamic hologram rendition, and realization of flat optics with reconfigurable focal lengths. Previously, electrically tunable conducting oxide-based reflectarray metasurfaces have demonstrated dynamic phase control of reflected light with a maximum phase shift of 184 degrees (Nano Lett. 2016, 16, 5319). Here, we introduce a dual-gated reflectarray metasurface architecture that enables much wider (>300 degrees) phase tunability. We explore light-matter interactions with dual-gated metasurface elements that incorporate two independent voltage-controlled MOS field effect channels connected in series to form a single metasurface element that enables wider phase tunability. Using indium tin oxide (ITO) as the active metasurface material and a composite hafnia/alumina gate dielectric, we demonstrate a prototype dual-gated metasurface with a continuous phase shift from 0 to 303 degrees and a relative reflectance modulation of 89% under applied voltage bias of 6.5 V.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available