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arXiv · 1304.3257

Controlling a Nanowire Spin-Orbit Qubit via Electric-Dipole Spin Resonance

Rui Li·J. Q. You·C. P. Sun·Franco Nori
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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}=\sqrt{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.

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Rui Li, J. Q. You, C. P. Sun, Franco Nori. 2013-09-04. Controlling a Nanowire Spin-Orbit Qubit via Electric-Dipole Spin Resonance. https://doi.org/10.1103/physrevlett.111.086805

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