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arXiv · 1812.11503

Extended crossover from Fermi liquid to quasi-antiferromagnet in the half-filled 2D Hubbard model

Fedor Šimkovic IV·J. P. F. LeBlanc·Aaram J. Kim·Youjin Deng·N. V. Prokof'ev·B. V. Svistunov·Evgeny Kozik
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Abstract

The ground state of the Hubbard model with nearest-neighbor hopping on the square lattice at half filling is known to be that of an antiferromagnetic (AFM) band insulator for any on-site repulsion. At finite temperature, the absence of long-range order makes the question of how the interaction-driven insulator is realized nontrivial. We address this problem with controlled accuracy in the thermodynamic limit using self-energy diagrammatic determinant Monte Carlo and dynamical cluster approximation methods and show that development of long-range AFM correlations drives an extended crossover from Fermi liquid to insulating behavior in the parameter regime that precludes a metal-to-insulator transition. The intermediate crossover state is best described as a non-Fermi liquid with a partially gapped Fermi surface.

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Fedor Šimkovic IV, J. P. F. LeBlanc, Aaram J. Kim, Youjin Deng, N. V. Prokof'ev, B. V. Svistunov, Evgeny Kozik. 2020-02-01. Extended crossover from Fermi liquid to quasi-antiferromagnet in the half-filled 2D Hubbard model. https://doi.org/10.1103/physrevlett.124.017003

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