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arXiv · 0905.0707

Unconventional metallic conduction in two-dimensional Hubbard-Wigner lattices

S. Fratini·J. Merino
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Abstract

The interplay between long-range and local Coulomb repulsion in strongly interacting electron systems is explored through a two-dimensional Hubbard-Wigner model. An unconventional metallic state is found in which collective low-energy excitations characteristic of the Wigner crystal induce a flow of electrical current despite the absence of one-electron spectral weight at the Fermi surface. Photoemission experiments on certain quarter-filled layered molecular crystals should observe a gap in the excitation spectrum whereas optical spectroscopy should find a finite Drude weight indicating metallic behavior.

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S. Fratini, J. Merino. 2009-09-02. Unconventional metallic conduction in two-dimensional Hubbard-Wigner lattices. https://doi.org/10.1103/physrevb.80.165110

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