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arXiv · 1006.2371

Exchange cotunneling through quantum dots with spin-orbit coupling

J. Paaske·A. Andersen·K. Flensberg
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Abstract

We investigate the effects of spin-orbit interaction (SOI) on the exchange cotunneling through a spinful Coulomb blockaded quantum dot. In the case of zero magnetic field, Kondo effect is shown to take place via a Kramers doublet and the SOI will merely affect the Kondo temperature. In contrast, we find that the breaking of time-reversal symmetry in a finite field has a marked influence on the effective Anderson, and Kondo models for a single level. The nonlinear conductance can now be asymmetric in bias voltage and may depend strongly on direction of the magnetic field. A measurement of the angle dependence of finite-field cotunneling spectroscopy thus provides valuable information about orbital, and spin degrees of freedom and their mutual coupling.

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J. Paaske, A. Andersen, K. Flensberg. 2010-06-11. Exchange cotunneling through quantum dots with spin-orbit coupling. https://doi.org/10.1103/physrevb.82.081309

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