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Title: Gate-tunable optical filter based on conducting oxide metasurface heterostructure
A gate-tunable plasmonic optical filter incorporating a sub- wavelength patterned metal–insulator–metal metasurface heterostructure is proposed. An additional thin transparent conducting oxide (TCO) layer is embedded in the insulator layer to form a double metal–oxide-semiconductor configu- ration. Heavily n-doped indium tin oxide (ITO) is em- ployed as the TCO material, whose optical property can be electrically tuned by the formation of a thin active ep- silon-near-zero layer at the ITO–oxide interfaces. Full-wave electromagnetic simulations show that amplitude modula- tion and shift of transmission peak are achievable with 3–5 V applied bias, depending on the application. Moreover, the modulation strength and transmission peak shift increase with a thinner ITO layer. This work is an essential step toward a realization of next-generation compact photonic/ plasmonic integrated devices.  more » « less
Award ID(s):
1752295
PAR ID:
10084077
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Optics letters
Volume:
44
Issue:
15
ISSN:
1539-4794
Page Range / eLocation ID:
3653-3656
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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