Coherent spin dynamics of excitons in quantum wells

Abstract
Coherent spin dynamics of excitons in quantum wells is investigated theoretically. Resonant and nonresonant excitation conditions are considered. The single-particle hole spin-flip mechanism within the exciton is always the dominant cause for breaking the exchange coupling. The two-dimensional confinement and low temperature are the most important factors which stabilize the hole spin orientation within the exciton. The experimental observations reported previously are interpreted.