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Glass-Like Heat Conduction in High-Mobility Crystalline Semiconductors

J. L. Cohn·G. S. Nolas·V. Fessatidis·T. H. Metcalf·G. A. Slack
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Abstract

The thermal conductivity of polycrystalline semiconductors with type-I clathrate hydrate crystal structure is reported. Ge clathrates (doped with Sr and/or Eu) exhibit lattice thermal conductivities typical of amorphous materials. Remarkably, this behavior occurs in spite of the well-defined crystalline structure and relatively high electron mobility ($\sim 100 cm^2/Vs$). The dynamics of dopant ions and their interaction with the polyhedral cages of the structure are a likely source of the strong phonon scattering.

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J. L. Cohn, G. S. Nolas, V. Fessatidis, T. H. Metcalf, G. A. Slack. 1998-12-23. Glass-Like Heat Conduction in High-Mobility Crystalline Semiconductors. https://doi.org/10.1103/physrevlett.82.779

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