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arXiv · 0704.0980

Spin state mixing in InAs double quantum dots

A. Pfund·I. Shorubalko·K. Ensslin·R. Leturcq
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Abstract

We quantify the contributions of hyperfine and spin-orbit mediated singlet-triplet mixing in weakly coupled InAs quantum dots by electron transport spectroscopy in the Pauli spin blockade regime. In contrast to double dots in GaAs, the spin-orbit coupling is found to be more than two orders of magnitudes larger than the hyperfine mixing energy. It is already effective at magnetic fields of a few mT, where deviations from hyperfine mixing are observed.

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A. Pfund, I. Shorubalko, K. Ensslin, R. Leturcq. 2007-04-07. Spin state mixing in InAs double quantum dots. https://doi.org/10.1103/physrevb.76.161308

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