Dynamics of the emission spectra of semiconductor quantum dot (QD) lasers generating on two quantum states has been experimentally studied. Being pumped with 30-ns current pulses, a QD laser ceased to generate 2-5 ns after switch-on and exhibited a pause up to 10 ns or longer, depending on the pumping pulse amplitude. After the subsequent switch-on, the laser generated short (200-300 ps) pulses of emission from the excited state of QDs followed by minima of comparable duration (dark pulses) corresponding to the ground-state emission. This behavior is explained in terms of the laser Q-switching due to the charge carrier density redistribution between the excited and ground states.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)