Berlin 2018 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 22: Superconductivity: Topological Defects in Superconductors and Magnets (joint session TT/MA)
TT 22.9: Vortrag
Montag, 12. März 2018, 17:15–17:30, HFT-FT 101
Vortex motion and change inside the superconducting phase of the ferromagnetic superconductor UCoGe — •Beilun Wu1, Dai Aoki2,3, and Jean-Pascal Brison2 — 1Universidad Autonoma de Madrid, Spain — 2CEA/University of Grenoble Alps, France — 3Tohoku University, Japan
Ferromagnetic superconductors can show equal spin pairing superconductivity, in form, for example, of a p-wave pair wave function. Among the different candidates, the U-based single crystalline systems stand out because of the real coexistence between the superconducting and ferromagnetic order, and their numerous interesting properties, such as the unusual upper critical field and the field-induced re-entrant superconductivity. Recent measurements show that superconductive pairing is remarkably sensitive to the external magnetic field. However, it is unknown if the magnetic field induces strong difference in the pairing interaction in different parts of the phase diagram. Here we address this issue by a combined study of thermal and electrical transport in UCoGe, under magnetic field up to 15T. We observe that the resistive transition width considerably sharpens in the high field region. In addition, it lies at a lower temperature than the bulk transition observed in the thermal conductance. This shows strongly enhanced vortex mobility in this high field region, in which a freezing transition from a vortex liquid to a glass-like or solid lattice might occur. Meanwhile a sudden change in thermal conductivity is observed inside the superconducting phase. Altogether these results suggest a field-induced change in the superconducting phase. *supported by ERC Pnicteyes