Active tuning of mid-infrared metamaterials by electrical control of carrier densities

Center for Integrated Nanotechnologies (CINT), Sandia National Laboratories, PAlbuquerque, New Mexico 87185, USA.
Optics Express (Impact Factor: 3.49). 01/2012; 20(2):1903-11. DOI: 10.1364/OE.20.001903
Source: PubMed


We demonstrate electrically-controlled active tuning of mid-infrared metamaterial resonances using depletion-type devices. The depletion width in an n-doped GaAs epilayer changes with an electric bias, inducing a change of the permittivity of the substrate and leading to frequency tuning of the resonance. We first present our detailed theoretical analysis and then explain experimental data of bias-dependent metamaterial transmission spectra. This electrical tuning is generally applicable to a variety of infrared metamaterials and plasmonic structures, which can find novel applications in chip-scale active infrared devices.

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Available from: Igal Brener, Sep 12, 2014
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