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Exact Drude weight for the one-dimensional Hubbard model at finite temperatures

Satoshi Fujimoto·Norio Kawakami
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Abstract

The Drude weight for the one-dimensional Hubbard model is investigated at finite temperatures by using the Bethe ansatz solution. Evaluating finite-size corrections to the thermodynamic Bethe ansatz equations, we obtain the formula for the Drude weight as the response of the system to an external gauge potential. We perform low-temperature expansions of the Drude weight in the case of half-filling as well as away from half-filling, which clearly distinguish the Mott-insulating state from the metallic state.

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Satoshi Fujimoto, Norio Kawakami. 1997-10-29. Exact Drude weight for the one-dimensional Hubbard model at finite temperatures. https://doi.org/10.1088/0305-4470%2F31%2F2%2F008

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