Two-Beam Coupling Measurements of Grating Phase in a Photorefractive Polymer
Abstract
We investigate in detail the grating properties of a recently discovered organic photorefractive polymer as a function of electric field using two-beam coupling. We present measurements of index and absorption grating phase relative to the intensity interference pattern as well as the amplitude of both the absorption and index gratings. We find that in low electric fields, a weak in-phase grating (possible photochromic) and the low electro-optic coefficient prevent observation of a phase shifted photorefractive grating. However, at moderate to high electric fields, a much stronger photorefractive index grating with phase shift approaching 90 degree dominates. The field dependence of the index grating phase is discussed in terms of a standard photorefractive model. The presence of an index grating with a 90 degree phase shift at high fields provides strong evidence that these polymers are indeed photorefractive.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 25, 1991
- Accession Number
- ADA243746
Entities
People
- C. A. Walsh
- W. E. Moerner
Organizations
- International Business Machines Corporation (Armonk, NY)