Magnetoresistance Study of Some RENi2B2C Borocarbides

The influence of magnetic field up to 130 kOe on normal-state resistance was investigated at 1.5≤T≤300 K for several RENi2B2C compounds (RE=Lu, Yb, Tm, Ho) prepared using a `high pressure–high temperature' technique. A positive magnetoresistance was observed for LuNi2B2C based on nonmagnetic Lu3+. However, for the compounds with localized magnetic moments (Ho3+, Tm3+, Yb3+), the magnetoresistance was negative being qualitatively different for various RENi2B2C compounds. Possible reasons for this difference are discussed. Some preliminary results on the Hall-effect of the YbNi2B2C compound are also presented and compared with ones previously obtained for YNi2B2C.