Lattice dynamics and reduced thermal conductivity of filled skutterudites

Journal Article · Sat Apr 01 00:00:00 EST 2000 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.61.R9209· OSTI ID:20215840

Feldman, J L ^[1]; Singh, D J ^[1]; Mazin, I I ^[1]; Mandrus, D ^[2]; Sales, B C ^[2]

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1. Code 6391, Naval Research Laboratory, Washington, D.C. 20375-5345 (United States)
2. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

The great reduction in thermal conductivity of skutterudites upon filling the ''void'' sites with rare-earth (RE) ions is key to their favorable thermoelectric properties but remains to be understood. Using lattice dynamic models based on first-principles calculations, we address the most popular microscopic mechanism, reduction via rattling ions. The model withstands inelastic neutron scattering and specific-heat measurements, and refutes hypotheses of an anharmonic RE potential and of two distinct localized RE vibrations of disparate frequencies. It does indicate a strong hybridization between bare La vibrations and certain Sb-like phonon branches, suggesting anharmonic scattering by harmonic RE motions as an important mechanism for suppression of heat conductivity. (c) 2000 The American Physical Society.

• OSTI ID: 20215840
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 61, Issue 14; Other Information: PBD: 1 Apr 2000; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LATTICE PARAMETERS
THERMAL CONDUCTIVITY
VOIDS
THERMOELECTRIC PROPERTIES
VIBRATIONAL STATES
COBALT COMPLEXES
RHODIUM COMPOUNDS
RHENIUM COMPOUNDS
IRIDIUM COMPOUNDS
PHOSPHORUS COMPOUNDS
ARSENIC COMPOUNDS
ANTIMONY COMPOUNDS
NEUTRON DIFFRACTION
SPECIFIC HEAT
INELASTIC SCATTERING
EXPERIMENTAL DATA
THEORETICAL DATA