Ultralong dephasing time in ingaas quantum dots

Abstract

We measure a dephasing time of several hundred picoseconds at low temperature in the ground-statetransition of strongly confined InGaAs quantum dots, using a highly sensitive four-wave mixing technique. Between 7 and 100 K the polarization decay has two distinct components resulting in a non-Lorentzian line shape with a lifetime-limited zero-phonon line and a broadband from elastic exciton-acoustic phonon interactions. © 2001 The American Physical Society.