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arXiv · 2507.12608

Suppression of Thermal Conductivity via Singlet-Dominated Scattering in TmFeO$_3$

M. L. McLanahan·D. Lederman·A. P. Ramirez
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Abstract

We measured the thermal conductivity of the rare-earth orthoferrites, $R$FeO$_3$, where $R$ = Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb from 3 K to 300 K and see an anomalous strong suppression for TmFeO$_3$ over most of the temperature range. Using a Debye thermal transport model, we demonstrate that this suppression is due to resonant scattering between phonons and the Tm$^{3+}$ $4f$ singlet crystal field levels. The implications of these results are discussed in context of thermal conductivity studies in quantum magnets.

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M. L. McLanahan, D. Lederman, A. P. Ramirez. 2025-07-16. Suppression of Thermal Conductivity via Singlet-Dominated Scattering in TmFeO$_3$. https://doi.org/10.1103/zc9q-8q95

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