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arXiv · 0708.2592

Triplet-singlet relaxation in semiconductor single and double quantum dots

K. Shen·M. W. Wu
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Abstract

We study the triplet-singlet relaxation in two-electron semiconductor quantum dots. Both single dots and vertically coupled double dots are discussed. In our work, the electron-electron Coulomb interaction, which plays an important role in the electronic structure, is included. The spin mixing is caused by spin-orbit coupling which is the key to the triplet-singlet relaxation. We show that the selection rule widely used in the literature is incorrect unless near the crossing/anticrossing point in single quantum dots. The triplet/singlet relaxation in double quantum dots can be markedly changed by varying barrier height, inter-dot distance, external magnetic field and dot size.

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K. Shen, M. W. Wu. 2007-11-27. Triplet-singlet relaxation in semiconductor single and double quantum dots. https://doi.org/10.1103/physrevb.76.235313

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