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arXiv · 0808.2364

First order Mott transition at zero temperature in two dimensions: Variational plaquette study

Matthias Balzer·Bumsoo Kyung·David Sénéchal·A. -M. S. Tremblay·Michael Potthoff
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Abstract

The nature of the metal-insulator Mott transition at zero temperature has been discussed for a number of years. Whether it occurs through a quantum critical point or through a first order transition is expected to profoundly influence the nature of the finite temperature phase diagram. In this paper, we study the zero temperature Mott transition in the two-dimensional Hubbard model on the square lattice with the variational cluster approximation. This takes into account the influence of antiferromagnetic short-range correlations. By contrast to single-site dynamical mean-field theory, the transition turns out to be first order even at zero temperature.

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Matthias Balzer, Bumsoo Kyung, David Sénéchal, A. -M. S. Tremblay, Michael Potthoff. 2008-11-18. First order Mott transition at zero temperature in two dimensions: Variational plaquette study. https://doi.org/10.1209/0295-5075/85/17002

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