Europhys. Lett.
Volume 75, Number 5, September 2006
Page(s) 797 - 803
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 21 July 2006
Europhys. Lett., 75 (5), pp. 797-803 (2006)
DOI: 10.1209/epl/i2006-10167-8

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

V. Ravi Chandra1, S. Rao2 and D. Sen1

1  Centre for High Energy Physics, Indian Institute of Science - Bangalore 560012, India
2  Harish-Chandra Research Institute - Chhatnag Road, Jhusi, Allahabad 211019, India

received 13 March 2006; accepted in final form 7 July 2006
published online 21 July 2006

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.

73.63.Nm - Quantum wires.
72.15.Qm - Scattering mechanisms and Kondo effect.
73.23.-b - Electronic transport in mesoscopic systems.

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