Electro-optic properties of Ba0.8Sr0.2TiO3 thin film

Electro-optic properties of Ba0.8Sr0.2TiO3 (BST) film with a thickness of 1 μm deposited on the MgO (001) substrate by the rf sputtering have been studied. Structural features of the film were identified by X-ray diffraction method. It was shown, that the BST film exhibited a predominantly linear EO behavior under the applied static electric field, that have been explained according to the strong compressive stresses in the film. The polarization distribution across the gap between the electrodes when electric field is applied was also investigated experimentally and calculated. The linear EO coefficient of Ba0.8Sr0.2TiO3 film with a thickness of 1 μm film was found to be rc = 99.4 p.m./V, that is promising for various EO applications, for example, high performance EO modulator.