Abstract

Illumination of a photorefractive iron-doped barium-calcium titanate crystal (Ba_0.77Ca_0.23TiO₃, BCT) with an oscillating interference pattern generates oscillating photo currents. These non-steady-state photocurrents arise from the interaction of a space-charge field with a vibrating photoconductivity pattern. However, a second harmonic signal of the oscillating photocurrents is observed in BCT, which is present without any space-charge field. The main features of the new effect can be explained by assuming that a dynamic, i.e. time-dependent, bulk photovoltaic effect exists.

© 1999 Optical Society of America