High field paramagnetic Meissner effect in Mo_100−xRe_x alloy superconductors

We have performed an experimental study on the temperature and field dependence of magnetization of a series of superconducting Mo_100−xRe_x alloys. Our studies reveal the presence of high field paramagnetic effect (HFPME) in these low temperature superconductors. The results of our studies indicate that the HFPME in the Mo_100−xRe_x alloys is related to the inhomogeneous distribution of strong and weak flux-line pinning centres, and the flux-compression resulting due to the same while cooling down the samples in the presence of high magnetic fields. The results are complemented by the studies on the temperature dependence of the electrical resistivity and heat capacity of these alloys in different constant magnetic fields. We compare our findings with the studies reported in literature on both low T_C and high T_C superconductors. (paper)