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arXiv · cond-mat/9510144

Spin Stiffness in the Hubbard model

J. M. J. van Leeuwen·M. S. L. du Croo de Jongh·P. J. H. Denteneer
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Abstract

The spin stiffness $ρ_{\rm s}$ of the repulsive Hubbard model that occurs in the hydrodynamic theory of antiferromagnetic spin waves is shown to be the same as the thermodynamically defined stiffness involved in twisting the order parameter. New expressions for $ρ_{\rm s}$ are derived, which enable easier interpretation, and connections with superconducting weight and gauge invariance are discussed.

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J. M. J. van Leeuwen, M. S. L. du Croo de Jongh, P. J. H. Denteneer. 1995-10-25. Spin Stiffness in the Hubbard model. https://doi.org/10.1088/0305-4470%2F29%2F1%2F008

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