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.