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arXiv · 0804.3314

T=0 heavy fermion quantum critical point as an orbital selective Mott transition

Lorenzo De Leo·Marcello Civelli·Gabriel Kotliar
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Abstract

We describe the T=0 quantum phase transition in heavy fermion systems as an orbital selective Mott transition (OSMT) using a cluster extension of dynamical mean field theory. This transition is characterized by the emergence of a new intermediate energy scale corresponding to the opening of a pseudogap and the vanishing of the low-energy hybridization between light and heavy electrons. We identify the fingerprint of Mott physics in heavy electron systems with the appearance of surfaces in momentum space where the self-energy diverges and we derive experimental consequences of this scenario for photoemission, compressibility, optical conductivity, susceptibility and specific heat.

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Lorenzo De Leo, Marcello Civelli, Gabriel Kotliar. 2009-01-18. T=0 heavy fermion quantum critical point as an orbital selective Mott transition. https://doi.org/10.1103/physrevlett.101.256404

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