Epitaxial films of Nd<sup>3+</sup>:GGG and Cr<sup>4+</sup>:GGG for the use in neodymium lasers
An efficient technology was developed for growing the gadolinium gallium garnet (GGG) single-crystal films doped with Nd3+ or Cr and Ca ions. The films with thickness up to 100 μm have been grown by liquid-phase epitaxy method both on small (5-8 mm) and big sizes (up to 76 mm in diameter) undoped GGG substrates. The study of absorption, luminescence spectra and optical losses at the wave length of 1 μm was carried as a function of growth process temperature and melt-solution composition. We demonstrated that Cr4+ centers have been realized in epifilms and these films may be used as passive Q-switches for laser systems.