Abstract
We measured spectral hole burning in an optical-absorption spectrum of a bound exciton (,X) in high-purity GaAs at 1.8 K. Precise temperature-controlled semiconductor lasers with a lasing wavelength accuracy of less than 0.001 nm are used as wavelength-tunable pump-and-probe light sources in the hole-burning experiments. The homogeneous linewidth of the bound exciton is determined from the burned hole spectral width. The dipole dephasing time estimated from the measured half width of the burned hole is 300 ps, which is more than an order of magnitude longer than the value reported for two-dimensional excitons in a GaAs quantum well. Such a long value of for bound excitons is due to exciton localization or, more specifically, the reduction in the optical-dipole scattering rate is due to zero-dimensional exciton confinement. © 1996 The American Physical Society.
- Received 25 January 1996
DOI:https://doi.org/10.1103/PhysRevB.54.4702
©1996 American Physical Society