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Spin relaxation rates in quasi-one-dimensional coupled quantum dots

C. L. Romano·P. I. Tamborenea·S. E. Ulloa
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Abstract

We study theoretically the spin relaxation rate in quasi-one-dimensional coupled double semiconductor quantum dots. We consider InSb and GaAs-based systems in the presence of the Rashba spin-orbit interaction, which causes mixing of opposite-spin states, and allows phonon-mediated transitions between energy eigenstates. Contributions from all phonon modes and coupling mechanisms in zincblende semiconductors are taken into account. The spin relaxation rate is shown to display a sharp, cusp-like maximum as function of the interdot-barrier width, at a value of the width which can be controlled by an external magnetic field. This remarkable behavior is associated with the symmetric-antisymmetric level splitting in the structure.

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C. L. Romano, P. I. Tamborenea, S. E. Ulloa. 2005-08-12. Spin relaxation rates in quasi-one-dimensional coupled quantum dots. https://doi.org/10.1103/physrevb.74.155433

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