  We investigate the properties of cuprate superconductors subject to applied
current, using modified Gutzwiller projected d-wave BCS states. The parent
states include quasiparticle and quasihole pockets, of variationally determined
size, generated by the current. We identify two different mechanisms for the
destruction of superconductivity at the critical current: at high hole doping
(x>0.15) the pockets grow and completely destroy the gap, in a BCS-like
mechanism; in the underdoped regime, the superfluid stiffness vanishes at a
maximal phase twist with pairing still intact. This result is indicative of a
pseudogapped "normal" state which retains pairing correlations. The critical
current as a function of doping displays a dome shape, similar to Tc. We
predict unique signatures of the current induced Fermi pockets that can be seen
in angle resolved photo emission spectroscopy.
