ABSTRACT Heteroepitaxial barium strontium titanate (Ba0.7Sr0.3TiO3 or BST) thin films were successfully grown on (LaAlO3)0.3(Sr2AlTaO6)0.35 (LSAT) (001) using pulsed laser deposition. X-ray diffraction characterization revealed that the films have a good crystalline quality and a pure perovskite structure. The in-plane ferroelectric properties of the films were studied using interdigital electrodes (IDE). The film exhibited a ferroelectric state at room temperature with the remnant polarization P r = 10.5 μC/cm2. A large linear electro-optic effect was observed in the Ba0.7Sr0.3TiO3 thin film in a transverse geometry at a wavelength of 632.8 nm using a modified Sénarmont method. The linear electro-optic coefficient r c of the Ba0.7Sr0.3TiO3 thin film was found to be 125.0 × 10−12 m/V, which is very promising for modulator applications.
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