Near-band-gap refractive index of GaSb

Abstract

We have measured the refractive index of GaSb by ellipsometry for the wavelength region below band gap ranging from 1.75 to 2.5 mu m. As far as we know, this is the first measurement for this wavelength region using this technique. There is a lack of agreement amongst the previous values reported in the literature for this material, where other techniques have been used. We describe the approach used here to obtain the refractive index from the ellipsometry parameters and then compare our results with the ones previously reported.