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Local moment formation in quantum point contacts

Kenji Hirose·Yigal Meir·Ned S. Wingreen
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Abstract

Spin-density-functional theory of quantum point contacts (QPCs) reveals the formation of a local moment with a net of one electron spin in the vicinity of the point contact - supporting the recent report of a Kondo effect in a QPC. The hybridization of the local moment to the leads decreases as the QPC becomes longer, while the onsite Coulomb-interaction energy remains almost constant.

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Kenji Hirose, Yigal Meir, Ned S. Wingreen. 2002-11-27. Local moment formation in quantum point contacts. https://doi.org/10.1103/physrevlett.90.026804

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