Hydrodynamic relation in 2D Heisenberg antiferromagnet in a field

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.

5*(1-ε) pages, 5 figures

References in corpus (3)

• Magnon Decay in Noncollinear Quantum Antiferromagnets
• Quantum Heisenberg antiferromagnets in a uniform magnetic field: nonanalytic magnetic field dependence of the magnon spectrum
• Effects of an external magnetic field on the gaps and quantum corrections in an ordered Heisenberg antiferromagnet with Dzyaloshinskii-Moriya anisotropy

Cited by in corpus (2)

• Spontaneous Magnon Decays
• Field-induced decay dynamics in square-lattice antiferromagnet