We have measured the I-V curves of Tl2Ba2CaCu2O8 thin films at differe
nt temperatures in fixed magnetic field. The curves collapsed nicely o
nto two branches by plotting V/I/\T-T-g\(nu(z-1)) vs. I/T\T-g-T\(2 nu)
, with the temperature T-g, critical exponents nu and z determined fro
m experiments. When T < 0.9T(g), the I-V curves collapsed onto a strai
ght line by plotting log (R/R(min)) vs. -(I-min/I)(mu) with the expone
nt mu in the range of 0.27 to 0.50. These characteristics support the
existence of a continuous phase transition at T-g from vortex-liquid t
o vortex-glass phase in Tl2Ba2CaCu2O8.