The pseudogap Fermi-Bose Kondo model

2002/09/30 by Matthias Vojta, Marijana Kircan
Physics and Astronomy · #cond-mat.str-el #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevlett.90.157203

published as Phys. Rev. Lett. 90, 157203 (2003) · 4 pages, 3 figs, (v2) conclusions regarding EDMFT modified, (v3) final version as published

arxiv created 2003/04/17 · arxiv updated 2009/11/30

Abstract

We consider a magnetic impurity coupled to both fermionic quasiparticles with a pseudogap density of states and bosonic spin fluctuations. Using renormalization group and large-N calculations we investigate the phase diagram of the resulting Fermi-Bose Kondo model. We show that the Kondo temperature is strongly reduced by low-energy spin fluctuations, and make connections to experiments in cuprate superconductors. Furthermore we derive an exact exponent for the critical behavior of the conduction electron T matrix, and propose our findings to be relevant for certain scenarios of local quantum criticality in heavy-fermion metals.

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