Glass-like Thermal-Transport in Symmetry-Broken Clathrates

Abstract

We present the quantitative interpretation for the glass-like behavior of thermal conductivities $\kappa (T)$ 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 $\kappa (T)$ between the $p$-type and the $n$-type $\beta$-BGS found recently by K. Suekuni et al. [Phys. Rev. B, 77 (2008) 235119.]

References in corpus (4)

• Vibrational instability, two-level systems and Boson peak in glasses
• Glasslike vs. crystalline thermal conductivity in carrier-tuned Ba8Ga16X30 clathrates (X = Ge, Sn)
• Cage-size control of guest vibration and thermal conductivity in Sr8Ga16Si30-xGex
• Interacting Dipoles in Type-I Clathrates: Why Glass-like though Crystal?

Cited by in corpus (2)

• Phonon-glass electron-crystal thermoelectric clathrates: Experiments and theory
• Significance of Off-Center Rattling for Emerging Low-lying THz Modes in type-I Clathrates