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Finite temperature Drude weight of an integrable Bose chain

Michael Bortz
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Abstract

We study the Drude weight $D(T)$ at finite temperatures $T$ of an integrable bosonic model where the particles interact via nearest-neighbour coupling on a chain. At low temperatures, $D(T)$ is shown to be universal in the sense that this region is equivalently described by a Gaussian model. This low-temperature limit is also relevant for the integrable one-dimensional Bose gas. We then use the thermodynamic Bethe ansatz to confirm the low-temperature result, to obtain the high temperature limit of $D(T)$ and to calculate $D(T)$ numerically.

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Michael Bortz. 2006-06-02. Finite temperature Drude weight of an integrable Bose chain. https://doi.org/10.1088/1742-5468%2F2006%2F08%2Fp08016

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