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Temperature Derivative of the Superfluid Density in the Attractive Hubbard model

F. F. Assaad·W. Hanke·D. J. Scalapino
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Abstract

Based on extensions of the grand-canonical Quantum Monte-Carlo algorithm to incorporate magnetic fields, we provide numerical data confirming the existence of a Kosterlitz-Thouless transition in the attractive Hubbard model. Here, we calculate the temperature derivative of the superfluid density, to pin down the transition. Away from half-band filling, the above quantity, shows a response which increases with lattice size at the transition temperature. In contrast, such a signal is not observed for the case of a half-band filling.

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F. F. Assaad, W. Hanke, D. J. Scalapino. 1993-10-13. Temperature Derivative of the Superfluid Density in the Attractive Hubbard model. https://doi.org/10.1103/physrevb.49.4327

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