Spectral dependence of external reflection switching from indium antimonide

We demonstrate a novel InSb optical switch that relies on an increasing absorption mechanism and uses only the surface reflection. Observations of external switching of the reflectivity of the InSb surface have been made. In this study the switching or pump beam was from a pulsed CO2 laser. The polarity of the switched out signal, the probe beam, was found to depend on the wavelength of the probe beam. This novel spectral dependence was used to demonstrate several optical logic elements.