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The pseudogap Fermi-Bose Kondo model

Matthias Vojta·Marijana Kircan
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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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Matthias Vojta, Marijana Kircan. 2003-04-17. The pseudogap Fermi-Bose Kondo model. https://doi.org/10.1103/physrevlett.90.157203

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