Growth of Nd:potassium gadolinium tungstate (KGW) thin-film waveguides by pulsed laser deposition

Thin Nd-doped potassium gadolinium tungstate [KGW or KGd(WO4)2] films are grown by pulsed laser deposition by ablation of a stoichiometric monocrystal target. Rutherford backscattering, x-ray diffraction, atomic force microscopy, and waveguide propagation analyses are performed. The as-grown films are optically active, as evidenced by the photoluminescence spectra centered at 1.068 µm. In some of the films, fine photoluminescence spectra between Stark levels are observed