Nd3+:GGG and Cr4+:GGG epitaxial films for neodymium lasers

An efficient technology was developed for growing the gadolinium gallium garnet (GGG) single-crystal films doped with Nd 3+ or Cr and Ca ions. The films with thickness up to 100 µm have been grown by liquid-phase epitaxy method on undoped GGG substrates of small and big sizes (5–8 mm and up to 76 mm in diameter, respectively). The dependence of absorption, luminescence spectra and optical losses at the wavelength of 1 µm on growth temperature and melt-solution composition was studied. We demonstrated that Cr 4+ centers have been implemented in epitaxial films and these films may be used as passive Q-switches for laser systems.