Dynamics of stimulated emission and gain saturation in InAs quantum dot amplifiers

摘要

The dynamics of stimulated emission and gain saturation are studied for optically pumped InAs quantum dot (QD) amplifiers, using excitation into the GaAs barrier by two degenerate pump and probe laser pulses. The non-linear emission from QDs excited by the pump pulse is further amplified by the probe excitation. By varying the delay between the two pulses a very fast decay of the QD excited state emission is measured and notably slower dynamics for the QD ground state is observed, which also exhibits gain saturation andrecovery.