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A multi-channel fixed point for a Kondo spin coupled to a junction of Luttinger liquids

V. Ravi Chandra·Sumathi Rao·Diptiman Sen
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Abstract

We study a system of an impurity spin coupled to a junction of several Tomonaga-Luttinger liquids using a renormalization group scheme. For the decoupled S-matrix at the junction, there is a range of Kondo couplings which flow to a multi-channel fixed point for repulsive inter-electron interactions; this is associated with a characteristic temperature dependence of the spin-flip scatterings. If the junction is governed by the Griffiths S-matrix, the Kondo couplings flow to a strong coupling fixed point where all the wires are decoupled.

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V. Ravi Chandra, Sumathi Rao, Diptiman Sen. 2006-03-15. A multi-channel fixed point for a Kondo spin coupled to a junction of Luttinger liquids. https://doi.org/10.1209/epl%2Fi2006-10167-8

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