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arXiv · 1602.08990

A DMFT+CTQMC Investigation of Strange Metallicity in Local Quantum Critical Scenario

Swagata Acharya·M S Laad·A Taraphder
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Abstract

Strange metallicity is now a pseudonym for a novel metallic state exhibiting anomalous infra-red (branch-cut) continuum features in one and two particle responses. Here, we employ dynamical mean-field theory (DMFT) using very low-temperature continuous-time-quantum Monte-Carlo (CTQMC) solver for an extended periodic Anderson model (EPAM) model to investigate unusual magnetic fluctuations in the strange metal. We show how extinction of Landau quasiparticles in the orbital selective Mott phase (OSMP) leads to (i) qualitative explication of strange transport features and (ii) anomalous quantum critical magnetic fluctuations due to critical liquid-like features in dynamical spin fluctuations, in excellent accord with data in some f-electron systems.

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Swagata Acharya, M S Laad, A Taraphder. 2016-02-29. A DMFT+CTQMC Investigation of Strange Metallicity in Local Quantum Critical Scenario. https://doi.org/10.1088/1742-6596/759/1/012037

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