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arXiv · 0707.0820

Magnetic-order induced phonon splitting in MnO from far-infrared spectroscopy

T. Rudolf·Ch. Kant·F. Mayr·A. Loidl
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Abstract

Detailed far-infrared spectra of the optical phonons are reported for antiferromagnetic MnO. Eigenfrequencies, phonon damping and effective plasma frequencies are studied as a function of temperature. Special attention is paid to the phonon splitting at the antiferromagnetic phase transition. The results are compared to recent experimental and theoretical studies of the spin-phonon coupling in frustrated magnets, which are explained in terms of a spin-driven Jahn-Teller effect, and to ab initio and model calculations, which predict phonon splitting induced by magnetic order.

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T. Rudolf, Ch. Kant, F. Mayr, A. Loidl. 2007-10-15. Magnetic-order induced phonon splitting in MnO from far-infrared spectroscopy. https://doi.org/10.1103/physrevb.77.024421

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