Growth of crystalline doped beta-alumina thin films by laser ablation

Crystalline thin films of sodium beta-alumina and beta-aluminogallate for optical applications have been deposited onto various single-crystal substrates by the pulsed laser deposition technique. Films with a smooth surface morphology were obtained by using Cr-doped targets. Despite Na loss in the films with respect to the target composition, the p-alumina crystalline phase was grown al elevated temperature (700-800 degrees C), and highly textured (001) films were obtained, whatever the substrates: MgO, ZrO2, Al2O3, or Si. The optical properties were studied by measuring the refractive index of the films and performing the emission spectrum of the Cr3+ ions, providing results very similar to those of the bulk single-crystalline material.