Optical properties of epitaxial (Ba_0.39Sr_0.61)₆Ti₂Nb₈O₃₀ thin films grown by pulsed laser deposition

Epitaxial (Ba_0.39Sr_0.61)₆Ti₂Nb₈O₃₀ (BSTN) thin films have been prepared on MgO (001) substrates by pulsed laser deposition technique. Their structural qualities and surface morphology were studied by X-ray diffraction (XRD) and scanning electron microscopy. XRD indicates that single crystalline BSTN layers with (001) orientation perpendicular to the substrate plane were obtained. Optical studies by ellipsometric and optical transmittance spectra measurements were carried out. The optical constants (refractive index n and extinction coefficient k) of the BSTN film have been determined. - Highlights: • High-quality epitaxial (Ba_0.39Sr_0.61)₆Ti₂Nb₈O₃₀ (BSTN) films have been prepared. • The structural qualities and surface morphology of BSTN film were studied. • The optical constants of BSTN film were characterized