2000 character limit reached
Electron-hole spin flip-flop in semiconductor quantum dots (1311.3615v2)
Published 14 Nov 2013 in cond-mat.mes-hall and quant-ph
Abstract: We use temporally resolved intensity cross-correlation measurements to identify the biexciton-exciton radiative cascades in a negatively charged QD. The polarization sensitive correlation measurements show unambiguously that the excited two electron triplet states relax non-radiatively to their singlet ground state via a spin non conserving flip-flop with the ground state heavy hole. We explain this mechanism in terms of resonant coupling between the confined electron states and an LO phonon. This resonant interaction together with the electron-hole exchange interaction provides an efficient mechanism for this, otherwise spin-blockaded, electronic relaxation.