Optical and electro-optic anisotropy of epitaxial Ba0.7Sr0.3TiO3 thin films

The anisotropic optical and electro-optic properties of ferroelectric Ba0.7Sr0.3TiO3 thin films, deposited on highly transparent single-crystal MgO (001), (011), and (111) substrates using pulsed laser deposition, were investigated. The experimental results show a strong correlation between optical, electro-optic properties, and the orientation of Ba0.7Sr0.3TiO3 thin films. The linear electro-optic coefficient r(c) of the (001), (011), and (111)-oriented Ba0.7Sr0.3TiO3 thin films are 99.1, 15.7, and 87.8 pm/V, respectively. Such a correlation may be attributed to the orientation dependent distribution and magnitude of spontaneous polarization.