Figure 1:
(a): dV/dI curves for vortexvortex interactions
(right to left) A_{v} = 0.01, 0.1, 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5, 6.
The peak in dV/dI increases in magnitude with decreasing A_{v}.
Inset to (a): Voltagecurrent V(I) curves for the A_{v} values listed
above.
The depinning transition shifts to higher driving
currents f_{d} and becomes more abrupt as A_{v} decreases.
(b): Voltage noise power S_{0} versus f_{d} for the A_{v}
values listed above. In each case the noise power peaks
during the plastic
flow regime. Inset to (b): Maximum noise power S_{max} as a function
of A_{v}. The peak value of S_{max} corresponds to
A_{v} ≈ 0.75, the same A_{v} at which the system crosses
between smectic and coupled channel behavior at high drives.
(c): Fraction of sixfold coordinated vortices P_{6} as a function
of f_{d} for values of A_{v} listed above.
At zero drive and strong VL coupling,
P_{6} ∼ 1 since the VL is fieldcooled.
The lowest value of P_{6} at each A_{v} corresponds exactly to the
peak in dV/dI. The VL eventually reorders to P_{6} ∼ 1 only
when A_{v} ≥ 1. For A_{v} ≤ 0.75,
P_{6} saturates at a value below 1.
Inset to (c): Velocity distribution functions D(v_{x})
for (1) plastic, (2) smectic,
and (3) coupled channel phases.
