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arXiv · 1309.0554

Interaction effects in Aharonov-Bohm-Kondo Rings

Yashar Komijani·Ryosuke Yoshii·Ian Affleck
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Abstract

We study the conductance through an Aharonov-Bohm ring, containing a quantum dot in the Kondo regime in one arm, at finite temperature and arbitrary electronic density. We develop a general method for this calculation based on changing basis to the screening and non-screening channels. We show that an unusual term appears in the conductance, involving the connected 4-point Green's function of the conduction electrons. However, this term and terms quadratic in the ${\rm T}$-matrix can be eliminated at sufficiently low temperatures, leading to an expression for the conductance linear in the Kondo T-matrix. Explicit results are given for temperatures high compared to the Kondo temperature.

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Yashar Komijani, Ryosuke Yoshii, Ian Affleck. 2013-11-14. Interaction effects in Aharonov-Bohm-Kondo Rings. https://doi.org/10.1103/physrevb.88.245104

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