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arXiv · 1111.5371

Transport criticality in triangular lattice Hubbard model

Toshihiro Sato·Kazumasa Hattori·Hirokazu Tsunetsugu
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Abstract

We study electric transport near the Mott metal-insulator transition. Optical conductivity of the half-filled Hubbard model on a triangular lattice is calculated based on a cellular dynamical mean field theory including vertex corrections inside the cluster. By investigating the spectrum at low frequencies, we find that a Drude peak on the metallic side smoothly connects to an "ingap" peak on the insulating side. The optical weight of these peaks exhibits a critical behavior with power-law near the Mott critical end point, $|D-D^*|\propto|U-U^*|^{1/δ}$. We find that the critical exponent $1/δ$ differs from the exponents in the thermodynamics.

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Toshihiro Sato, Kazumasa Hattori, Hirokazu Tsunetsugu. 2011-11-24. Transport criticality in triangular lattice Hubbard model. https://doi.org/10.1143/jpsj.81.083703

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