Fine structural splitting and exciton spin relaxation in single InAs quantum dots

We have studied the exciton spin dynamics in single InAs quantum dots (QDs) with different exciton fine structural splitting (FSS) by transient luminescence measurements. We have established the correlation between exciton spin relaxation rate and the energy splitting of the FSS when FSS is nonzero and found that the spin relaxation rate in QD increases with a slope of 8.8x10(-4) ns(-1) mu eV(-1). Theoretical analyses based on the phonon-assisted relaxations via the deformation potential give a reasonable interpretation of the experimental results.

National Basic Research Program of China 2007CB924904 Chinese Academy of Sciences KICX2.YW.W09-1 This work is supported partly by the National Basic Research Program of China under Grant No. 2007CB924904 and the Knowledge Innovation Program Project of Chinese Academy of Sciences under Grant No. KICX2.YW.W09-1.