Study of effective de-Gennes factor and effect of doping on superconductivity in rare-earth nickel borocarbide superconductors

Abstract

We theoretically study the effective de Gennes factor and effect of doping on the critical temperature in RNi2B2C (R = Ho). We formulate a mean-field Hamiltonian model where a BCS type of Cooper pair mechanism is considered. We self-consistently solve SC order parameter, AFM order parameter and dopant concentration. The de Gennes scaling on critical temperature and Neel temperature for different Nickel borocarbide compounds gives an idea about the competition between superconductivity and antiferromagnetism in rare earth quaternary borocarbide superconductors RNi2B2C. We study here the effect of doping on the parent borocarbide superconductor HoNi2B2C. We plot the effective de-Gennes factor vs. SC critical temperature for the pseudo quaternary borocarbide compound HoxLa1-xNi2B2C for different dopant concentrations which agrees well with experimental findings.