Resistivity and superconducting transition temperature dependence in the La1−xUxSn3 system

Abstract

It has been established that the magnetic character of U alloys and intermetallic compounds is strongly correlated with the average U–U separation. The electrical resistivity, superconducting transition temperature, and room-temperature lattice parameter have been measured for La1−xUxSn3 to examine manifestations of a changing U–U separation on the magnetic character of the U ion in this system. The properties were measured from 1.5 to 300 K for x=0 to 1. The temperature dependence of the total electrical resistivity minus the phonon contribution for x<0.3 has a negative temperature coefficient at high temperatures and passes through a maximum in the vicinity of 50 K. For x>0.3 and x<0.8, the maximum in this quantity is shifted to lower temperatures and for x=0.9 and 1.0, the resistivity minus phonon contributions decrease monotonically with decreasing temperatures and goes to zero at T2. The x dependence of the lattice parameter follows Vegard’s Law over the entire region. The x dependence of the superconducting transition temperature and the x and temperature dependence of the electrical resistivity are presented.