Several photorefractive crystals such as LiNbO3 or BaTiO3 can be used for optical information storage as well as key elements for optical signal processing due to their unique property, viz., their refractive index varies according to their incident light distribution. Thus, we can construct phase gratings inside the crystals by using interference of two light beams. The index grating amplitude Δn can be computed from the equation derived from the Band Transport model for the photorefractive effect. Experimentally, the value of Δn can be estimated from counting the number of peaks in the curve for the diffraction efficiency as a function of time under the phase matching condition. Its precision is about 13%. Here we report a new method improving the measurement precision to about 1% by adding the measurement for the diffraction efficiency as a function of angle mismatch. This precise measurement of Δn allows us to quantify photorefractive effect with greater precision.
|Number of pages||5|
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|State||Published - 1999|
|Event||Proceedings of the 1999 Photorefractive Fiber and Crystal Devices: Materials, Optical Properties, and Applications V - Denver, CO, USA|
Duration: 18 Jul 1999 → 19 Jul 1999