We experimentally demonstrate fast switching of light propagation and phase conjugate generation in a BaTiO3:Ce crystal with a high efficiency. The switching mechanism is based on the phase mismatch in photorefractive beam coupling between an incident beam and a fanning beam. The phase mismatch is induced by an externally applied electric field via Pockels effect. In our experiment we obatin a voltage-generator-determined switching time of the order of 10 ?s. The required voltage to reduce the output phase conjugate power by more than 90% is about only 100 volts for our 3.8 mm-thick crystal.