Measurements of the spin relaxation rate at low magnetic fields in a quantum dot

S. Amasha, K. MacLean, Iuliana Radu, D. M. Zumbuhl, M. A. Kastner, M. P. Hanson, A. C. Gossard

Published 2006-07-05Version 1

We measure the relaxation rate $W \equiv T_{1}^{-1}$ of a single electron spin in a quantum dot at magnetic fields from 7 T down to 1.75 T, much lower than previously measured. At 1.75 T we find that $T_{1}$ is 170 ms. We find good agreement between our measurements and theoretical predictions of the relaxation rate caused by the spin-orbit interaction, demonstrating that spin-orbit coupling can account for spin relaxation in quantum dots.