Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur Graph Search.
We report specific-heat measurements at magnetic fields up to 20 T on the recently discovered superconductor SmFeAsO0.85F0.15. The B-T diagram of a polycrystalline SmFeAsO0.85F0.15 sample with T-c=46 K was investigated. The temperature dependence of B-c2 was extracted from the specific-heat curves; the corresponding B-c2(T=0) value derived from the Werthamer-Helfand-Hohenberg formula being 150 T. Based on magnetization measurements up to 9 T, a first estimation of the field dependence of the inductive critical current J(c) is given. Evidence for granularity is found. The presence of a peak effect is reported, suggesting a crossover in the vortex dynamics, in analogy to the behavior observed in high T-c cuprates.
Henrik Moodysson Rønnow, Arnaud Magrez, Ivica Zivkovic, Nagabhushan Ganesh Hegde