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Spin exchange in quantum rings and wires in the Wigner-crystal limit

Michael M. Fogler·Eugene Pivovarov
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Abstract

We present a controlled method for computing the exchange coupling in strongly correlated one-dimensional electron systems. It is based on the asymptotically exact relation between the exchange constant and the pair-correlation function of spinless electrons. Explicit results are obtained for thin quantum rings with realistic Coulomb interactions, by calculating this function via a many-body instanton approach.

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Michael M. Fogler, Eugene Pivovarov. 2005-10-10. Spin exchange in quantum rings and wires in the Wigner-crystal limit. https://doi.org/10.1088/0953-8984%2F18%2F1%2Fl02

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