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arXiv · 1108.1817

Two-Impurity Kondo Model: Spin-Orbit Interactions and Entanglement

Henrik Johannesson·David F. Mross·Erik Eriksson
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Abstract

Motivated by proposals to employ RKKY-coupled spins as building blocks in a solid-state quantum computer, we analyze how the RKKY interaction in a 2D electron gas is influenced by spin-orbit interactions. Using a two-impurity Kondo model with added Dresselhaus and Rashba spin-orbit interactions we find that spin-rotational invariance of the RKKY interaction - essential for having a well-controllable two-qubit gate - is restored when tuning the Rashba coupling to have the same strength as the Dresselhaus coupling. We also discuss the critical properties of the two-impurity Kondo model in the presence of spin-orbit interactions, and extract the leading correction to the block entanglement scaling due to these interactions.

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Henrik Johannesson, David F. Mross, Erik Eriksson. 2011-08-08. Two-Impurity Kondo Model: Spin-Orbit Interactions and Entanglement. https://doi.org/10.1142/s0217984911026796

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