Spin relaxation due to spin-orbit coupling in multi-electron quantum dots

We show that the number of electrons confined in a semiconductor quantum dot has a strong influence over the Rashba and Dresselhaus spin-orbit (SO) admixture. This can be exploited to improve the lifetime of spin excitations, as compared to the usual one- and two-electron devices. The physical mechanisms reducing SO admixture are discussed, and numerical results for realistic weakly confined GaAs/AlGaAs dots are reported. (c) 2007 Elsevier B.V. AD rights reserved.