Picosecond pump probe measurements on waveguides containing a single GaAs/GaAlAs quantum well have enabled us to determine for the first time both electron and hole escape times from biased quantum wells. Contributions from excitonic saturation and field screening by photogenerated carriers can be clearly identified in the nonlinear transition signal and are quantitatively modeled. Preliminary analysis suggests that thermally assisted escape is dominant at room temperature, but discrepancies are found with conventional thermionic emission models.
|Number of pages||3|
|Journal||Applied Physics Letters|
|Publication status||Published - 27 Jul 1992|