Abstract
Transport measurements, including magnetoresistivity, Hall resistivity, thermal conductivity, and thermopower, and an assessment of the dimensionless thermoelectric figure of merit (Formula presented) below room temperature are reported on a polycrystalline sample of the strongly correlated electron material (Formula presented) Neutron diffraction measurements are presented, which reveal large amplitude thermal vibrations of the Yb ion, consistent with speculations that the ion is weakly bound in an oversized atomic “cage” formed in the skutterudite crystal structure. Infrared spectroscopy measurements reveal a resonance in the dissipative part of the optical conductivity (Formula presented) which develops below (Formula presented) the characteristic temperature for the Yb ion valence fluctuations. The frequency dependence of the optical constants is suggestive of a hybridization band gap in the quasiparticle density of states at low temperatures.
Original language | English |
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Pages (from-to) | 4608-4614 |
Number of pages | 7 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 61 |
Issue number | 7 |
DOIs | |
State | Published - 2000 |