RESISTIVITY AND THERMOELECTRIC-POWER OF CU-SUBSTITUTED YNI(2-X)CU(X)B2C SUPERCONDUCTOR

We measured the electrical resistivity and the thermoeletric power(TEP ) of YNi2-xCuxB2C with different Cu concentration x. The resistivity d ata show that T-c decreases systematically and the scattering of elect rons by structural disorder increases upon Cu substitution. The TEP ha s a nonlinear temperature dependency, which suggests the modified mixe d valent character(mixed valency plus diffusion contribution). However , the discrepancy between TEP data and the best-fit curve of the modif ied mixed valent character for the underdoped samples at low temperatu re indicates that the additional scattering mechanism, such as phonon drag, is involved.