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Spin-orbit coupling and intrinsic spin mixing in quantum dots

C. F. Destefani·S. E. Ulloa·G. E. Marques
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Abstract

Spin-orbit coupling effects are studied in quantum dots in InSb, a narrow-gap material. Competition between different Rashba and Dresselhaus terms is shown to produce wholesale changes in the spectrum. The large (and negative) $g$-factor and the Rashba field produce states where spin is no longer a good quantum number and intrinsic flips occur at moderate magnetic fields. For dots with two electrons, a singlet-triplet mixing occurs in the ground state, with observable signatures in intraband FIR absorption, and possible importance in quantum computation.

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C. F. Destefani, S. E. Ulloa, G. E. Marques. 2003-07-01. Spin-orbit coupling and intrinsic spin mixing in quantum dots. https://doi.org/10.1103/physrevb.69.125302

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