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arXiv · 1103.1155

Spin-wave energy dispersion of a frustrated spin-1/2 Heisenberg antiferromagnet on a stacked square lattice

Kingshuk Majumdar
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Abstract

Effects of interlayer coupling and spatial anisotropy on spin-wave excitation spectra of a three-dimensional spatially anisotropic, frustrated spin-$\half$ Heisenberg antiferromagnet (HAFM) is investigated for the two ordered phases using second-order spin-wave expansion. We show that the second-order corrections to the spin-wave energies are significant and find that the energy spectra of the three-dimensional HAFM shares similar qualitative features with the energy spectra of the two-dimensional HAFM on a square lattice. We also discuss the features that can provide experimental measures for the strength of the interlayer coupling, spatial anisotropy parameter, and magnetic frustration.

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Kingshuk Majumdar. 2011-03-06. Spin-wave energy dispersion of a frustrated spin-1/2 Heisenberg antiferromagnet on a stacked square lattice. https://doi.org/10.1088/0953-8984%2F23%2F11%2F116004

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