Accession Number:

ADA359207

Title:

MBE Growth and Characterization of GaN/AlN Structures Under Hydrostatic Pressure

Descriptive Note:

Final rept. 1 Jun 93-31 May 97

Corporate Author:

OKLAHOMA STATE UNIV STILLWATER DEPT OFPHYSICS

Personal Author(s):

Report Date:

1997-07-30

Pagination or Media Count:

7.0

Abstract:

We present the results of a series of studies on the optical properties of GaN and AlGaNGaN heterostructures using a variety of spectroscopic techniques. Strain effects were found to have a strong influence in determining the energies of excitonic transitions. The observations of spectral features associated with the transitions involving the ground and excited exciton states make it possible to directly estimate binding energy for the excitons in GaN. Optical pumping experiments were performed on AlGaNGaN separate confinement heterostructures SCH grown on sapphire by MBE and SiC by MOCVD. The threshold pumping powers were found to be an order of magnitude lowere than that for regular GaN epilayers. Nonlinear four-wave-mixing experiments were carried out in both femtosecond and picosecond regimes to study the intensity and time response of scattering efficiency, as well as the pump-induced nonlinear refractive index change.

Subject Categories:

  • Inorganic Chemistry
  • Crystallography
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE