Abstract
Transport properties of single-crystalline samples prepared with an excess of Ga are presented. The excess Ga does not only produces p-type transport properties but also a thermal conductivity (κ) that, unlike in any other samples reported in the literature, is similar to that of the iso-structural and These observations disagree with the commonly made assumption that κ of and at very low temperatures is determined by phonons scattered from guest atom tunneling states, since such states are believed to be absent in Instead we propose that phonon charge carrier scattering must be considered in order to explain κ at the low temperatures. The transport data also suggest that the resonant scattering, which dominates at intermediate temperatures, strongly depends on the charge carrier concentration.
- Received 13 October 2003
DOI:https://doi.org/10.1103/PhysRevB.69.045107
©2004 American Physical Society