| Many proposed optical computing designs involve parallel arrays of lasers, lenses, diffractive optical elements, and photodiodes to perform high speed, massively parallel computing operations. To date, these designs conspicuously avoid arrays of active optical modulators. The development of thin film transverse optical modulator arrays, that modulate light passing transversely through the layers, is a current topic of interest.; Pb0.91La0.09Zr0.65Ti0.35O 3 ceramics exhibit quadratic electro-optic coefficients on the order of 10--16 m2/V2 and have been used in bulk electro-optical devices. Recently, pulsed laser ablation techniques have facilitated oxide film growth of PLZT and other complex ceramics. Single layer PLZT optical devices have been fabricated, but light passing transversely through a PLZT film layer experiences insufficient optical path length to allow useful modulation. However, current oxide film growth techniques also allow the growth of multilayer oxide structures. Electro-optic oxide materials may now be introduced into thin-film optical resonator structures, to enhance optical modulation properties.; This thesis has studied the growth and optical behavior of complex PLZT multilayer structures on GaAs. Magnesium oxide was used as a buffer and capping layer to allow pulsed laser ablation of perovskites on GaAs substrates. Single and double PLZT/SrTiO3 structures have been grown and fabricated into optical modulator devices. Physical characterization has shown that these structures consist of discrete, phase-pure (001) oriented oxide layers, with a maximum 30nm RMS roughness on the top surface and a high defect density.; Electo-optical characterization was performed in reflection mode, normal incidence with 670nm laser light. Electrically induced birefringence in the PLZT layers resulted in measurable optical phase and amplitude modulation. A single frequency modulation of the PLZT layers resulted in substantial first harmonic optical modulation, which is direct evidence of the quadratic nature of the electro-optic effect in PLZT.; These devices may be considered as electro-optic Bragg interference structures. Theoretical modeling of electro-optic modulation in these structures has allowed the fitting of theory to experiment, and indicates that the PLZT material in these devices has a quadratic electro-optic constant R = 8.4 x 10 --17 m2/V2 and a linear electro-optic constant of R = 2.0 x 10--12 m/V. |
