We recorded a hologram in a photorefractive LiNbO3:Fe crystal with a two-color recording technique in transmission geometry. The holographic recording involves a light with wavelength 633nm for interference, and a light with wavelength 532nm for exciting. The short wavelength light excites more charges so that the holographic recording is affected, and the storage capacity (M-number) and the sensitivity vary accordingly. We found that the optimized intensity ratio of the interference lights and the exciting light is between 50 and 60. In the optimized conditions, the M number and the sensitivity are enhanced by 43 and 35%, respectively. Because the crystal we used is a typical iron-doped LiNbO3 crystal and the short wavelength exciting light source is inexpensive now, the proposed method is easy to be achieved in most holographic systems.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics