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arXiv · 0901.2957

Glass-like Thermal-Transport in Symmetry-Broken Clathrates

Eiji Kaneshita·Tsuneyoshi Nakayama
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Abstract

We present the quantitative interpretation for the glass-like behavior of thermal conductivities $κ(T)$ for type-I clathrate compounds involving off-centered guest ions. It is shown that the dipole-dipole interaction generated in cage/guest-ion systems is crucial to reproduce the characteristics of thermal conductivities for these symmetry-broken clathrates. The above scenario also explains well the difference of $κ(T)$ between the $p$-type and the $n$-type $β$-BGS found recently by K. Suekuni et al. [Phys. Rev. B, 77 (2008) 235119.]

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Eiji Kaneshita, Tsuneyoshi Nakayama. 2009-07-02. Glass-like Thermal-Transport in Symmetry-Broken Clathrates. https://doi.org/10.1209/0295-5075/86/56004

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