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arXiv · 1011.5303

Quantum Critical Phase and Lifshitz Transition in an Extended Periodic Anderson Model

M. S. Laad·S. Koley·A Taraphder
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Abstract

We study the quantum phase transition in $f$-electron systems as a quantum Lifshitz transition driven by selective Mott localization in a realistic extended Anderson lattice model. Using DMFT, we find that a quantum critical {\it phase} with anomalous $\omega/T$ scaling separates a heavy Landau-Fermi liquid from ordered phase(s). Fermi surface reconstruction occurs via the interplay between, and penetration of the Green function zeros to the poles, leading to violation of Luttinger's theorem in the selective-Mott phase . We show how this naturally leads to scale-invariant responses in transport. Our work is represents a specific (DMFT) realization of the hidden-FL and FL$^{*}$ theories, and holds promise for study of "strange" metal phases in quantum matter.

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M. S. Laad, S. Koley, A Taraphder. 2010-11-24. Quantum Critical Phase and Lifshitz Transition in an Extended Periodic Anderson Model. https://doi.org/10.1088/0953-8984%2F24%2F23%2F232201

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