  We study phase transitions and critical phenomena in nonequilibrium steady
states controlled by an electric field. We employ the D3/D7 model in the
presence of a charge density and electric field at finite temperatures. The
system undergoes the first-order and the second-order phase transitions under
the variation of the electric field in the presence of dissipation. We
numerically find that the critical exponents which we define for the
nonequilibrium phase transition in this model take the mean-field values.
