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arXiv · 1005.2106

Quantum critical behavior of electrons at the edge of charge order

Laura Cano-Cortes·Jaime Merino·Simone Fratini
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Abstract

We consider quantum critical points (QCP) in which quantum fluctuations associated with charge rather than magnetic order induce unconventional metallic properties. Based on finite-T calculations on a two-dimensional extended Hubbard model we show how the coherence scale T* characteristic of Fermi liquid behavior of the homogeneous metal vanishes at the onset of charge order. A strong effective mass enhancement reminiscent of heavy fermion behavior indicates the possible destruction of quasiparticles at the QCP. Experimental probes on quarter-filled layered organic materials are proposed for unveiling the behavior of electrons across the quantum critical region.

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Laura Cano-Cortes, Jaime Merino, Simone Fratini. 2010-06-17. Quantum critical behavior of electrons at the edge of charge order. https://doi.org/10.1103/physrevlett.105.036405

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