Interplay and optimization of decoherence mechanisms in the optical control of spin quantum bits implemented on a semiconductor quantum dot

摘要

We study the influence of the environment on an optically induced rotation ofa single electron spin in a charged semiconductor quantum dot. We analyze thedecoherence mechanisms resulting from the dynamical lattice response to thecharge evolution induced in a trion-based optical spin control scheme.Moreover, we study the effect of the finite trion lifetime and of theimperfections of the unitary evolution such as off-resonant excitations and thenonadiabaticity of the driving. We calculate the total error of the operationon a spin-based qubit in an InAs/GaAs quantum dot system and discuss possibleoptimization against the different contributions. We indicate the parameterswhich allow for coherent control of the spin with a single qubit gate error aslow as $10^{-4}$.