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arXiv · 0708.3125

Control of spin coherence in semiconductor double quantum dots

Y. Y. Wang·M. W. Wu
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Abstract

We propose a scheme to manipulate the spin coherence in vertically coupled GaAs double quantum dots. Up to {\em ten} orders of magnitude variation of the spin relaxation and {\em two} orders of magnitude variation of the spin dephasing can be achieved by a small gate voltage applied vertically on the double dot. Specially, large variation of spin relaxation still exists at 0 K. In the calculation, the equation-of-motion approach is applied to obtain the electron decoherence time and all the relevant spin decoherence mechanisms, such as the spin-orbit coupling together with the electron--bulk-phonon scattering, the direct spin-phonon coupling due to the phonon-induced strain, the hyperfine interaction and the second-order process of electron-phonon scattering combined with the hyperfine interaction, are included. The condition to obtain the large variations of spin coherence is also addressed.

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Y. Y. Wang, M. W. Wu. 2008-02-18. Control of spin coherence in semiconductor double quantum dots. https://doi.org/10.1103/physrevb.77.125323

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