We report systematic measurements of photoluminescence excitation spectra and dephasing times (T2's) on various excited states of hundreds of individual quantum dots (QDs). From the variation of T2's with the energy separation between excited states and the ground state (Erel), we identified two distinct regions of Erel where LO phonon emission and hole relaxation via LA phonon emission play as dominat dephasing mechanisms. We also found a clear evidence of significantly slow energy relaxation in the Erel range where these phonon emission processes are suppressed due to the reduction of interaction phase space.
|Number of pages||4|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2001 Jan 1|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics