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arXiv · 1411.3920

Magnetic order and spin excitations in layered Heisenberg antiferromagnets with compass-model anisotropies

A. A. Vladimirov·D. Ihle·N. M. Plakida
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Abstract

The spin-wave excitation spectrum, the magnetization, and the N\'{e}el temperature for the quasi-two-dimensional spin-1/2 antiferromagnetic Heisenberg model with compass-model interaction in the plane proposed for iridates are calculated in the random phase approximation. The spin-wave spectrum agrees well with data of Lanczos diagonalization. We find that the Neel temperature is enhanced by the compass-model interaction and is close to the experimental value for Ba2IrO4.

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A. A. Vladimirov, D. Ihle, N. M. Plakida. 2014-11-14. Magnetic order and spin excitations in layered Heisenberg antiferromagnets with compass-model anisotropies. https://doi.org/10.1134/s0021364014240163

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