https://doi.org/10.1140/epjb/e2005-00322-1
Doping dependence of the vortex glass and sublimation transitions in the high-Tc superconductor La2-xSrxCuO4 as determined from macroscopic measurements
1
Laboratory for Neutron Scattering, ETH Zurich and PSI Villigen, 5232 Villigen PSI, Switzerland
2
Departement of Physics, Hokkaido University, Sapporo 060-0810, Japan
Corresponding author: a gilardi@hispeed.ch
Received:
3
April
2005
Revised:
25
July
2005
Published online:
11
October
2005
Magnetization and ac-susceptibility measurements are used to
characterize the mixed phase of the high-temperature cuprate
superconductor La2-xSrxCuO4 over a large range of doping (0.075 0.20). The first order vortex lattice phase transition line
, the upper
critical field
and the second peak
have been
investigated up to high magnetic fields (8 Tesla applied perpendicular to the
planes).
Our results reveal a strong doping dependence of the magnetic phase diagram, which can mainly be
explained by the increasing anisotropy with underdoping.
Within our interpretation, the first order vortex lattice phase transition is due to the sublimation (rather than melting) of the vortex lattice into a gas of pancake vortices, whereas the second peak is related to the transition to a more disordered vortex glass state.
PACS: 74.25.Ha – Magnetic properties / 74.25.Qt – Vortex lattices, flux pinning, flux creep / 74.72.Dn – La-based cuprates
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005