Superconductivity of binary and ternary compounds of Bi

Binary and ternary compounds of Bi formed with 3d transition elements Ni, Co, Fe, and Cr have been studied. Resistance behavior at low temperatures shows two superconducting transitions, one between 4 and 5 K and the other at 10.3 K. Resistance data above Tc up to about 25 K reveal a temperature exponent of 2 for higher Tc samples and 3 when Tc is lower. ESR studies seem to indicate an increase in the density of states at EF. Results are discussed in terms of various models based on the Landau Fermi-liquid theory and the observed data are interpreted in terms of spin-density-fluctuation model