Enhanced critical currents of superconducting ErNi2B2C in the ferromagnetically ordered state
We report on transport and magnetization studies of the critical current in single crystal ErNi2B2C for applied fields below 4 kG. Below T approximately 2.5 K superconductivity coexists with weak ferromagnetism. We find that the critical currents are strongly enhanced for all field orientations in this ferromagnetic regime, corresponding to a threefold increase of the pinning force of the flux line lattice. We speculate that this increase is due to strong pair breaking by the ferromagnetism.
Gammel
PL
Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974, USA.
Barber
B
Lopez
D
Ramirez
AP
Bishop
DJ
Bud'ko
SL
Canfield
PC