Large Signal Gain Effects in Photorefractive Bi sub 12 Tio sub 20 at 633 nm,
Abstract
Bil2TiO20 (BTO) is a photorefractive material in the same structural class (sillenite) as Bil2SiO20 (BSO) and Bil2GiO20 (BGO). However, BTO offers some unique advantages over BSO and BGO: (1) larger electro-optic coefficient (5.7 pm/V)1, and (2) lower optical activity (6 deg/mm at 633 nm). Previous photorefractive measurements 3,4 have shown that gain coefficients on the order of 10 to 15/cm. can be produced through the use of an applied AC field. In this work we show that the largest gain values can only be obtained for large values of the pump/probe intensity ratio Beta. As Beta approaches unity (large signal regime), higher spatial order gratings become prominent, and the gain is reduced from its large-Beta value. Our results are similar to those obtained by other researchers for BS0 and GaAs with an applied field. We have analyzed this and related.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 22, 1992
- Accession Number
- ADP006760
Entities
People
- B. A. Wechler
- F. P. Strohkendl
- M. B. Klein
Organizations
- HRL Laboratories