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Spin-phonon coupling in ZnCr2Se4

T. Rudolf·Ch. Kant·F. Mayr·J. Hemberger·V. Tsurkan·A. Loidl
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Abstract

Spin-phonon coupling and magnetodielectric effects of ZnCr2Se4 were investigated by means of infrared (IR) spectroscopy as a function of temperature and magnetic field. ZnCr2Se4 is dominated by ferromagnetic exchange but undergoes antiferromagnetic order at T = 21 K. In the magnetically ordered phase the low-frequency IR active phonon splits, indicating strong dynamic anisotropy via magnetic exchange interactions. Antiferromagnetic order and concomitantly the phonon splitting is wiped out by external magnetic fields. Hence, ZnCr2Se4 is a prominent example of a spin-driven Jahn-Teller effect which can be fully suppressed in external magnetic fields.

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T. Rudolf, Ch. Kant, F. Mayr, J. Hemberger, V. Tsurkan, A. Loidl. 2006-11-02. Spin-phonon coupling in ZnCr2Se4. https://doi.org/10.1103/physrevb.75.052410

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