by: Glen R. Fox, Claude A.P. Muller, Matthius Kuhn, Nava J. Setter, Nguyen Hong Ky, Hans G. Limberger
Abstract: Miniature all-fiber phase modulators have been fabricated by integrating piezoelectric actuator coatings with telecommunication optical fibers. Evaporation and sputter deposition processes were used to grow thin film PbZrxTi1 – xO3 (PZT) and ZnO actuator structures directly on the surface of optical fibers. When an electric field is applied to the piezoelectric coating, a strain is produced in both the coating and the optical fiber. The strain induced in the optical fiber causes a change in the refractive index through the photoelastic effect. Electric field tuneable optical phase modulation was achieved by utilizing the optical path length changes in the optical fiber that are induced by the integrated actuator structure. Processes similar to those used for coating optical fibers were also used make micro-tubes of PZT and ZnO between 20 and 30 micrometers in diameter. The piezoelectric layers were deposited onto polyester fibers, which were subsequently burned away to leave behind a micro-tube. Actuator structures have been produced and show promise for micro-electro- mechanical applications.
