Spin relaxation in semiconductor quantum rings and dots—a comparative study

Abstract

We calculate spin relaxation times due to spin–orbit-mediated electron–phonon interactions forexperimentally accessible semiconductor quantum ring and dot architectures. We elucidate thedifferences between the two systems due to different confinement. The estimated relaxation times (atB = 1 T) are in the range between a few milliseconds to a few seconds. This high stability of spinin a quantum ring allows us to test it as a spin qubit. A brief discussion of quantum statemanipulations with such a qubit is presented.