Abstract
A study of the polarization properties of the exciton emission in is presented. Photoluminescence measurements are performed for light propagation perpendicular to the axis of a free standing layer grown by hydride vapor phase epitaxy. Emission from different polariton branches of the and free exciton states are identified for the and polarizations, respectively. The mixed-mode transverse-longitudinal state of the A exciton is also observed in the polarized spectra. Donor-bond excitons involving a hole from the A and B valence bands are clearly distinguished and are found to follow the optical selection rules of the free excitons. The temperature dependence of the emission intensities is also investigated and the exciton thermalization processes for both polarizations are discussed.
- Received 1 March 2004
DOI:https://doi.org/10.1103/PhysRevB.70.035210
©2004 American Physical Society