https://doi.org/10.1140/epjb/e2002-00373-8
Two-step flux penetration in classic antiferromagnetic superconductor
Institute of Low Temperature and Structure Research,
Polish Academy of Sciences, 50-950 Wrocław, PO Box 1410,
Poland
Corresponding author: a krzyszto@int.pan.wroc.pl
Received:
16
August
2002
Revised:
22
October
2002
Published online:
29
November
2002
The influence of antiferromagnetic order on the mixed
state of a superconductor may result in creation of spin-flop
domains along vortices. This may happen when an external magnetic
field is strong enough to flip over magnetic moments in the vortex
core from their ground state configuration. The formation of
domain structure causes modification of the surface energy
barrier, and creation of the new state in which magnetic flux
density is independent of the applied field. The modified surface
energy barrier has been calculated for parameters of the
antiferromagnetic superconductor DyMo6S8. The prediction
of two-step flux penetration process has been verified by precise
magnetization measurements performed on the single crystal of
DyMo6S8 at milikelvin temperatures. A characteristic
plateau on the virgin curve has been found and attributed
to the modified surface energy barrier. The end of the plateau
determines the critical field, which we call the second critical
field for flux penetration.
PACS: 74.60.-w – Type-II superconductivity / 74.25.Ha – Magnetic properties
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002