Abstract

Great interest has been exhibited recently in subpicosecond gain dynamics in optical amplifiers.^1,2 However, these dynamics are not yet fully understood. The long waveguide geometry of optical amplifiers (a few hundred micrometers) greatly adds to the confusion surrounding these subpicosecond dynamics, In this paper, we present subpicosecond gain dynamics of an optically excited, passive semiconductor of ≈1 µm thickness. By using this thin sample, we circumvent many of the problems associated with propagation and waveguide effects in optical amplifiers. We observe spectral hole-burning in the gain region, consistent with our many-body theoretical results.

© 1993 Optical Society of America