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arXiv · 1403.1743

Continuous Mott Transition in a Two-Dimensional Hubbard Model

Yuki Yanagi·Kazuo Ueda
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Abstract

We investigate nonmagnetic metal-insulator transition in the 1/5-depleted square lattice Hubbard model at half-filling within the 8-site cellular dynamical mean field theory. We find that a metal-insulator transition without any signatures of the first order transition, a continuous Mott transition, takes place in a certain range of parameters. The nature of the continuous Mott transition is nothing but a Lifshitz transition driven by the on-site Coulomb interaction. The renormalized matrix elements of hoppings and the spin-spin correlation functions reveal that physics of this transition is strong enhancement of the dimerization due to the non-local effects of electron-electron interaction.

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Yuki Yanagi, Kazuo Ueda. 2014-08-18. Continuous Mott Transition in a Two-Dimensional Hubbard Model. https://doi.org/10.1103/physrevb.90.085113

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