Abstract

We have investigated the new doubly color sensitive photorefractive crystal Bi₁₂Ti_0.76V_0.24O₂₀ by writing a hologram in green (λ = 0.51 µm, cw-argon laser) and reading it out in red (λ = 0.63 µm, cw-HeNe laser). It was found that the diffraction efficiency for the red beam is chaotically oscillating in time with a period of about 0.1 s between zero and some maximum. The diffraction efficiency for the red beam decayed smoothly after the green beam was switched off. These oscillations exist also for values of the diffraction efficiency as low as 0.1%, and therefore can not be explained by overmodulation of the refractive-index grating.

© 1991 Optical Society of America