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Direct Calculation of Spin-Stiffness for Spin-1/2 Heisenberg Models

J. Bonca·J. P. Rodriguez·J. Ferrer·K. S. Bedell
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Abstract

The spin-stiffness of frustrated spin-1/2 Heisenberg models in one and two dimensions is computed for the first time by exact diagonalizations on small clusters that implement spin-dependent twisted boundary conditions. Finite-size extrapolation to the thermodynamic limit yields a value of $0.14\pm 0.01$ for the spin-stiffness of the unfrustrated planar antiferromagnet. We also present a general discussion of the linear-response theory for spin-twists, which ultimately leads to the moment sum-rule.

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J. Bonca, J. P. Rodriguez, J. Ferrer, K. S. Bedell. 1994-05-24. Direct Calculation of Spin-Stiffness for Spin-1/2 Heisenberg Models. https://doi.org/10.1103/physrevb.50.3415

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