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arXiv · 1012.2988

Magnetic impurity in a $U(1)$-Spin Liquid with a Spinon Fermi-Surface

P. Ribeiro·P. A. Lee
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Abstract

We address the problem of a magnetic impurity in a two dimensional $U(1)$ spin liquid where the spinons have gap-less excitations near the Fermi-surface and are coupled to an emergent gap-less gauge field. Using a large N expansion we analyze the strong coupling behavior and obtain the Kondo temperature which was found to be the same as for a Fermi-liquid. In this approximation we also study the specific heat and the magnetic susceptibility of the impurity. These quantities present no deviations from the Fermi-liquid ones, consistent with the notion that the magnetic impurity is only sensitive to the local density of fermionic states.

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P. Ribeiro, P. A. Lee. 2010-12-14. Magnetic impurity in a $U(1)$-Spin Liquid with a Spinon Fermi-Surface. https://doi.org/10.1103/physrevb.83.235119

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