  In the mixed state of type II superconductors, vortices penetrate the sample
and form a correlated system due to the screening of supercurrents around them.
Interestingly, we can study this correlated system as a function of density and
driving force. The density, for instance, is controlled by the magnetic field,
B, whereas a current density j acts as a driving force F=jxB on all vortices.
The free motion of vortices is inhibited by the presence of an underlying
potential, which tends to pin the vortices. Hence, to minimize the pinning
strength we studied a superconducting glass in which the depinning current is
10 to 1000 times smaller than in previous studies, which enables us to map out
the complete phase diagram in this new regime. The diagram is obtained as a
function of B, driving current and temperature and led a remarkable set of new
results, which includes a huge peak effect, an additional reentrant depinning
phase and a driving force induced pinning phase.
