Optical properties of potassium lithium niobate films

Potassium lithium niobate (KLN) thin films have been deposited on fused sil ica and MgO from metallorganic compounds through a sol-gel process. X-ray d iffraction structure analysis has shown that KLN films crystallize into tet ragonal tungsten-bronze-type phase after appropriate annealing. Crystalliza tion of KLN films has a strong dependence on the structure of the substrate s. Polycrystalline KLN films were obtained on fused quartz, whereas oriente d KLN films have been achieved on MgO single crystal substrates. Optical st udies have indicated that the films were highly transparent in the visible- near infrared wavelength range and the absorption edges of the films are al so substrate-dependent. The films could support optical modes.