CaltechAUTHORS
  A Caltech Library Service

>270° phase shift in aluminum gate tunable conducting oxide metasurfaces for continuous optical beam steering at 1550 nm

Kafaie Shirmanesh, Ghazaleh and Sokhoyan, Ruzan and Pala, Ragip and Atwater, Harry A. (2018) >270° phase shift in aluminum gate tunable conducting oxide metasurfaces for continuous optical beam steering at 1550 nm. In: Photonic and Phononic Properties of Engineered Nanostructures VIII. Proceedings of SPIE. No.10541. Society of Photo-optical Instrumentation Engineers (SPIE) , Bellingham, WA, Art. No. 105410B. ISBN 9781510615687. http://resolver.caltech.edu/CaltechAUTHORS:20180705-164319479

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20180705-164319479

Abstract

In the last several years, metasurfaces have demonstrated promise as both flat optical elements to replace conventional three-dimensional components (prisms or lenses) as well as to access functions that are unachievable in conventional optics. To date, the functional performance of metasurfaces have typically been encoded at the time of fabrication, which fixes the achievable phase and amplitude for each elements in an array. However if actively controlled metasurface elements can be designed to dynamically control the phase shift and amplitude change imposed by each metasurface element, we could realize phased arrays to enable complex spatio-temporal wavefront engineering. We report here design and experimental demonstration of a tunable conducting oxide metasurface that achieves such active control by incorporating materials with voltage-tunable optical permivitties, such as indium tin oxide (ITO), into a metasurface [1]. We design a metasurface that consists of an aluminum back plane, HfO2 gate dielectric followed by a 14 nm thick ITO active layer, and a periodic array of aluminum patch antennas. We choose the dimensions of the Al antennas so that the antenna magnetic dipole resonance occurs at 1550 nm. By applying a gate bias between the Al antenna and ITO active layer, charge accumulation or depletion occurs at the ITO/HfO2 interface. This results in modulation of the ITO complex permittivity, thus altering the metasurface reflection phase and amplitude. The designed metasurface is capable of >270° phase shift. Our design enables independent control of each metasurface element enabling electrical control of the metasurface phase profile, which is an essential requirement for demonstration of continious beam steering.


Item Type:Book Section
Related URLs:
URLURL TypeDescription
https://doi.org/10.1117/12.2286384DOIArticle
ORCID:
AuthorORCID
Kafaie Shirmanesh, Ghazaleh0000-0003-1666-3215
Sokhoyan, Ruzan0000-0003-4599-6350
Atwater, Harry A.0000-0001-9435-0201
Additional Information:© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE).
Record Number:CaltechAUTHORS:20180705-164319479
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20180705-164319479
Official Citation:Ghazaleh Kafaie Shirmanesh, Ruzan Sokhoyan, Ragip Pala, Harry A. Atwater, ">270° phase shift in aluminum gate tunable conducting oxide metasurfaces for continuous optical beam steering at 1550 nm (Conference Presentation)", Proc. SPIE 10541, Photonic and Phononic Properties of Engineered Nanostructures VIII, 105410B (14 March 2018); doi: 10.1117/12.2286384; https://doi.org/10.1117/12.2286384
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:87578
Collection:CaltechAUTHORS
Deposited By: George Porter
Deposited On:06 Jul 2018 15:49
Last Modified:30 May 2019 17:58

Repository Staff Only: item control page