Plasmonic mid-infrared beam steering

We present a metal/semiconductor beam steering device for use in the mid-infrared wavelength range. We demonstrate how changing the frequency of the incident light results in a smoothly varying shift in the angular distribution of the transmitted beam, and we present an analysis of the beam profile for a number of different wavelengths. Finally we verify that a similar steering effect is achieved with fixed frequency incident light and a modification of the permittivity of the semiconductor substrate, ultimately resulting in a 3 degrees shift in the transmitted beam angle for minimal shifts in the semiconductor permittivity. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3431665]