Evidence for a transition from a bulk Meissner-state to a spontaneous vortex phase in RuSr${}_2$GdCu${}_2$O${}_8$ from DC magnetisation measurements

C. Bernhard, J. L. Tallon, E. Brücher +1

From magnetisation measurements we provide evidence that the ferromagnetic superconductor RuSr${}_2$GdCu${}_2$O${}_8$ with \QTR{it}{T}${}_c$=45 K and \QTR{it}{T}${}_M$=137 K exhibi…