Giant Spin Relaxation and Orientation Anisotropy inQuantum Wells

摘要

Relaxation and orientation anisotropy of electron and hole spins in semiconductorrnheterostructures is considered. Various mechanisms of spin relaxation are taken into account.rnIt is shown that, for the D’yakonov-Perel’ electron spin relaxation, three spin dephasingrntimes are different. The in-plane spin relaxation anisotropy can be giant in asymmetricalrnheterostructures if the Rashba and Dresselhaus terms are comparable. For the Elliot-Yafetrnmechanism, spin relaxation times are calculated. Both mechanisms are considered for holes inrnthe valence band as well. Electron spin orientation by external electric field due to Rashba andrnDresselhaus terms is investigated. We show that it is anisotropic and depends non-linearly onrnthe spin-orbit constants. Possible experiments to observe the predicted effects are discussed.