Ultrafast switch-off of an electrically pumpedInAs/GaAs quantum-dot laser

摘要

We report on the sub-picosecond switch-off of the emission ofan electrically pumped quantum dot (QD) laser with perturbation by a100 fs optical pulse. The observed effect is explained by unique propertiesof the QDs, namely by the fast modal gain saturation and localizationenhanced intraband absorption. The QD laser response is described interms of hot carrier absorption via intraband optical transitions leading tothe transient suppression of the laser mode and, hence, to the switch-off.We show a comparison to a quantum well laser diode, where this effect isnot seen.