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Fast initialization of the spin state of an electron in a quantum dot in the Voigt configuration

C. Emary·Xiaodong Xu·D. G. Steel·S. Saikin·L. J. Sham
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Abstract

We consider the initialization of the spin-state of a single electron trapped in a self-assembled quantum dot via optical pumping of a trion level. We show that with a magnetic field applied perpendicular to the growth direction of the dot, a near-unity fidelity can be obtained in a time equal to a few times the inverse of the spin-conserving trion relaxation rate. This method is several orders-of-magnitude faster than with the field aligned parallel, since this configuration must rely on a slow hole spin-flip mechanism. This increase in speed does result in a limit on the maximum obtainable fidelity, but we show that for InAs dots, the error is very small.

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C. Emary, Xiaodong Xu, D. G. Steel, S. Saikin, L. J. Sham. 2006-08-09. Fast initialization of the spin state of an electron in a quantum dot in the Voigt configuration. https://doi.org/10.1103/physrevlett.98.047401

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