John C. Marinace

Raman scattering in thin‐film waveguides

It is shown that Raman spectra can be obtained from thin films by using the films as waveguides for the exciting laser light and efficiently collecting the scattered light. We have applied this technique to single‐crystal GaN films epitaxially grown on c‐plate Al2O3. The measured polarized Raman spectra enable all the Raman active modes to be determined for the GaN (point group C6v).

Uniformly Polarized GaAs Laser Array

A structure is described which yields uniform polarization in the emitted light from an array of GaAs lasers. The exterior cleaved faces define a standard Fabry‐Perot structure, and a 2‐μ air space within the cavity inclined at the Brewster angle provides the necessary discrimination in gain between orthogonal modes to produce TE polarization (within ± 3°) for all lasers in the array.