ELECTRICAL-RESISTIVITY AND THERMOPOWER OF SINGLE-CRYSTAL RNI2B2C (R=DY, HO, ER, TM) MAGNETIC SUPERCONDUCTORS

The in-plane resistivity rho and thermopower S of single crystal RNi2B 2C (R=Dy, Ho, Er, Tm) has been measured from 4 to 300 K. The resistivi ty is linear in temperature from about 100 to 300 K, but the low-tempe rature dependence goes as T-p With p = 3.0, 2.6, 2.0, and 1.4, respect ively, from Dy to Tm, in comparison to the T-2 behavior previously rep orted for LuNi2B2C. The thermopower exhibits a region linear in T from about 100 to 300 K where the coefficient b scales by the de Gennes fa ctor (g-1)(2)J(J+1) for different R = Lu, Tm-Dy. The quantity S-b T is surprisingly similar in temperature dependence and magnitude for samp les with R = Y, Lu, Dy-Tm, suggesting a common, nonmagnetic contributi on to the thermopower of these compounds.