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Spin relaxation in diluted magnetic semiconductor quantum dots

W. Yang·K. Chang
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Abstract

Electron spin relaxation induced by phonon-mediated s-d exchange interaction in a II-VI diluted magnetic semiconductor quantum dot is investigated theoretically. The electron-acoustic phonon interaction due to piezoelectric coupling and deformation potential is included. The resulting spin lifetime is typically on the order of microseconds. The effectiveness of the phonon-mediated spin-flip mechanism increases with increasing Mn concentration, electron spin splitting, vertical confining strength and lateral diameter, while it shows non-monotonic dependence on the magnetic field and temperature. An interesting finding is that the spin relaxation in a small quantum dot is suppressed for strong magnetic field and low Mn concentration at low temperature.

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W. Yang, K. Chang. 2005-06-30. Spin relaxation in diluted magnetic semiconductor quantum dots. https://doi.org/10.1103/physrevb.72.075303

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