Strain Induced Optical Waveguiding and Polarization Conversion in Ferroelectric Substrates,
Abstract
A localized increase in the refractive index of ferroelectric crystals has been accomplished by the use of static strain induced from a surface film. The technique does not require alteration of substrate composition by diffusion or ion exchange. Optical waveguides have been produced by this method in LiNbO3, LiTaO3 and BaTiO3. This represents the first formation of waveguides in BaTiO3, which is ideally suited for making compact low-voltage polarization control guided-wave devices and optical filters due to its large r51 electrooptic coefficient. To produce an index increase, a thick film of SiO2 is deposited on the substrate surface at an elevated temperature then cooled to room temperature and patterned. The static strain resulting from the large thermal expansion mismatch between the substrate and film causes a localized index increase in the crystal beneath regions from which the SiO2 is removed, via the strain optic effect.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1992
- Accession Number
- ADP008073
Entities
People
- H. F. Taylor
- J. M. Marx
- O. Eknoyan
- V. P. Swenson
- Zikang Tang
Organizations
- Texas A&M University