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Strong damping of phononic heat current by magnetic excitations in SrCu_2(BO_3)_2

M. Hofmann·T. Lorenz·G. S. Uhrig·H. Kierspel·O. Zabara·A. Freimuth·H. Kageyama·Y. Ueda
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Abstract

Measurements of the thermal conductivity as a function of temperature and magnetic field in the 2D dimer spin system SrCu$_2$(BO$_3$)$_2$ are presented. In zero magnetic field the thermal conductivity along and perpendicular to the magnetic planes shows a pronounced double-peak structure as a function of temperature. The low-temperature maximum is drastically suppressed with increasing magnetic field. Our quantitative analysis reveals that the heat current is due to phonons and that the double-peak structure arises from pronounced resonant scattering of phonons by magnetic excitations.

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M. Hofmann, T. Lorenz, G. S. Uhrig, H. Kierspel, O. Zabara, A. Freimuth, H. Kageyama, Y. Ueda. 2001-10-18. Strong damping of phononic heat current by magnetic excitations in SrCu_2(BO_3)_2. https://doi.org/10.1103/physrevlett.87.047202

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