  In this article, we present evidence for the existence of vortex-solid/glass
(VG) to vortex-fluid (VF) transition in a type-II superconductor (SC), NbN. We
probed the VG to VF transition in both 2D and 3D films of NbN through studies
of magnetoresistance and current-voltage characteristics. The dynamical
exponents corresponding to this phase transition were extracted independently
from the two sets of measurements. The $H$-$T$ phase diagram for the 2D and 3D
SC are found to be significantly different near the critical point. In the case
of 3D SC, the exponent values obtained from the two independent measurements
show excellent match. On the other hand, for the 2D SC, the exponents obtained
from the two experiments were significantly different. We attribute this to the
fact that the characteristic length scale diverges near the critical point in a
2D SC in a distinctly different way from its 3D counterpart form scaling
behaviour.
