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arXiv · 1006.4784

Mott transition in the Hubbard model on the anisotropic kagomé lattice

Yuta Furukawa·Takuma Ohashi·Yohta Koyama·Norio Kawakami
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Abstract

We investigate the Mott transition in the anisotropic kagomé lattice Hubbard model using the cellular dynamical mean field theory combined with continuous-time quantum Monte Carlo simulations. By calculating the double occupancy and the density of states, we determine the interaction strength of the first-order Mott transition and show that it becomes small as the anisotropy increases. We also calculate the spin correlation functions and the single-particle spectrum, and reveal that the quasiparticle and magnetic properties change dramatically around the Mott transition; the spin correlations are strongly enhanced and the quasiparticle bands are deformed. We conclude that such dramatic changes are due to the enhancement of anisotropy associated with the relaxation of frustration around the Mott transition.

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Yuta Furukawa, Takuma Ohashi, Yohta Koyama, Norio Kawakami. 2010-06-26. Mott transition in the Hubbard model on the anisotropic kagomé lattice. https://doi.org/10.1103/physrevb.82.161101

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