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arXiv · 0704.3510

Coupling of phonons and spin waves in triangular antiferromagnet

Jung Hoon Kim·Jung Hoon Han
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Abstract

We investigate the influence of the spin-phonon coupling in the triangular antiferromagnet where the coupling is of the exchange-striction type. The magnon dispersion is shown to be modified significantly at wave vector (2pi,0) and its symmetry-related points, exhibiting a roton-like minimum and an eventual instability in the dispersion. Various correlation functions such as equal-time phonon correlation, spin-spin correlation, and local magnetization are calculated in the presence of the coupling.

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Jung Hoon Kim, Jung Hoon Han. 2007-07-02. Coupling of phonons and spin waves in triangular antiferromagnet. https://doi.org/10.1103/physrevb.76.054431

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