title: Controlling a nanowire spin-orbit qubit via electric-dipole spin resonance.
abstract: A semiconductor nanowire quantum dot with strong spin-orbit coupling (SOC) can be used to achieve a spin-orbit qubit. In contrast to a spin qubit, the spin-orbit qubit can respond to an external ac electric field, an effect called electric-dipole spin resonance. Here we develop a theory that can apply in the strong SOC regime. We find that there is an optimal SOC strength η(opt)=√2/2, where the Rabi frequency induced by the ac electric field becomes maximal. Also, we show that both the level spacing and the Rabi frequency of the spin-orbit qubit have periodic responses to the direction of the external static magnetic field. These responses can be used to determine the SOC in the nanowire.
authors.affiliation: Beijing Computational Science Research Center, Beijing 100084, China and Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.forename: J Q
authors.initials: JQ
authors.lastname: You
authors.forename: C P
authors.initials: CP
authors.lastname: Sun
authors.forename: Franco
authors.initials: F
authors.lastname: Nori