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arXiv · 0902.4455

Hydrodynamic relation in 2D Heisenberg antiferromagnet in a field

A. L. Chernyshev·M. E. Zhitomirsky
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Abstract

The spin-stiffness ρ_s of a 2D Heisenberg antiferromagnet depends non-analytically on external magnetic field. We demonstrate that the hydrodynamic relation between ρ_s, the uniform susceptibility χ, and the spin-wave velocity $c$ is not violated by such a behavior because similar non-analytic terms from all three quantities mutually cancel out. In this work, explicit expressions for the field-dependent spin stiffness and for the magnon velocity of the 2D square lattice antiferromagnet are obtained by direct calculation to order 1/S and in the whole range of magnetic fields.

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A. L. Chernyshev, M. E. Zhitomirsky. 2009-02-25. Hydrodynamic relation in 2D Heisenberg antiferromagnet in a field. https://doi.org/10.1103/physrevb.79.174402

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