Electrical transport in bismuth whiskers at millikelvin temperatures

The authors have investigated the electrical conductivity of 1-5 mu m thick bismuth whiskers at temperatures down to 20 mK, and in parallel and perpendicular magnetic fields up to 9 T. In parallel fields they searched for, but found no evidence of, triplet-paired multivalley superconductivity. In perpendicular fields H>0.5 T they observe a small temperature-dependent contribution to the resistivity on top of the large classical magnetoresistance; comparison with predicted electron-electron interaction effects suggests that the dominant conduction path is a two-dimensional surface layer.