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arXiv · 1508.07886

Mott Quantum Criticality in the Anisotropic 2D Hubbard Model

Benjamin Lenz·Salvatore R. Manmana·Thomas Pruschke·Fakher F. Assaad·Marcin Raczkowski
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Abstract

We present evidence for Mott quantum criticality in an anisotropic two-dimensional system of coupled Hubbard chains at half-filling. In this scenario emerging from variational cluster approximation and cluster dynamical mean-field theory, the interchain hopping $t_{\perp}$ acts as a control parameter driving the second-order critical end point $T_c$ of the metal-insulator transition down to zero at $t_{\perp}^{c}/t\simeq 0.2$. Below $t_{\perp}^{c}$, the volume of the hole and electron Fermi pockets of a compensated metal vanishes continuously at the Mott transition. Above $t_{\perp}^{c}$, the volume reduction of the pockets is cut off by a first-order transition. We discuss the relevance of our findings to a putative quantum critical point in layered organic conductors, whose location remains elusive so far.

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Benjamin Lenz, Salvatore R. Manmana, Thomas Pruschke, Fakher F. Assaad, Marcin Raczkowski. 2016-03-05. Mott Quantum Criticality in the Anisotropic 2D Hubbard Model. https://doi.org/10.1103/physrevlett.116.086403

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