Volume 85, Number 1, January 2009
Article Number 17002
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 07 January 2009
EPL, 85 (2009) 17002
DOI: 10.1209/0295-5075/85/17002

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

M. Balzer1, B. Kyung2, D. Sénéchal2, A.-M. S. Tremblay2 and M. Potthoff3

1   Institut für Theoretische Physik und Astrophysik, Universität Würzburg - Würzburg, Germany, EU
2   Département de physique and RQMP, Université de Sherbrooke - Québec, J1K 2R1 Canada
3   I. Institut für Theoretische Physik, Universität Hamburg - Hamburg, Germany, EU

received 19 August 2008; accepted in final form 27 November 2008; published January 2009
published online 7 January 2009

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.

71.10.-w - Theories and models of many-electron systems.
71.30.+h - Metal-insulator transitions and other electronic transitions.

© EPLA 2009