Heat and charge transport in YNi2B2C and HoNi2B2C single crystals


Heat and charge transport in YNi2B2C and HoNi2B2C single crystals

Schneider, M.; Gladun, A.; Kreyssig, A.; Wosnitza, J.; Petzold, V.; Rosner, H.; Behr, G.; Souptel, D.; Müller, K.-H.; Drechsler, S.-L.; Fuchs, G.

For a systematic investigation of the heat- and charge-transport properties of YNi2B2C and HoNi2B2C, single-crystal measurements of the electrical resistivity, the thermal conductivity, and the thermoelectric power were performed on the same samples. For HoNi2B2C, a local maximum of the Lorenz number at 20 K is evidently connected with the occurrence of magnetic fluctuations well above the ordering temperature. For the in-plane thermal conductivity, a kink near the superconducting transition was observed, consistent with an anisotropic gap or a multiband description. For both investigated borocarbides, the electrical resistance is isotropic. In contrast, the thermal conductivity shows a pronounced anisotropy. The thermoelectric power exhibits a minor anisotropy and can be well described by electron-diffusion and phonon-drag contributions over a wide temperature range. Based on an analysis of full-potential local-orbital calculations, a strong influence of the boron z position on the thermoelectric power has been
revealed.

  • Journal of Physics: Condensed Matter 20(2008), 175221

Permalink: https://www.hzdr.de/publications/Publ-11217
Publ.-Id: 11217