Optical guided modes and surface acoustic waves in GaN grown on (0001) sapphire substrates

The propagation of guided optical modes and surface acoustic waves in GaN l ayers grown on sapphire by MOCVD technique is experimentally studied. The e ffective refractive indices of guided optical modes are measured using the prism coupling technique, and the thickness and refractive indices of the l ayer are evaluated. The surface acoustic wave velocities are measured by ac oustooptic diffraction technique, revealing a strong acoustic dispersion. T he evaluation of GaN layer thickness from the SAW measurements is demonstra ted.