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arXiv · 1909.09335

Typicality-Based Variational Cluster Approach to Thermodynamic Properties of the Hubbard Model

Hisao Nishida·Ryo Fujiuchi·Koudai Sugimoto·Yukinori Ohta
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Abstract

We develop the variational-cluster-approximation method based on the thermal-pure-quantum-state approach and apply the method to the calculations of the thermodynamic properties of the Hubbard model, thereby obtaining the temperature dependence of the single-particle excitation spectra, entropy and specific heat, and order parameter of the antiferromagnetic phase efficiently. We thus demonstrate that the method developed here has a potential power for elucidating finite-temperature properties of strongly correlated electron systems.

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Hisao Nishida, Ryo Fujiuchi, Koudai Sugimoto, Yukinori Ohta. 2019-09-20. Typicality-Based Variational Cluster Approach to Thermodynamic Properties of the Hubbard Model. https://doi.org/10.7566/jpsj.89.023702

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