Epitaxial Nd-doped α-(Al1-xGax)2O3 films on sapphire for solid-state waveguide lasers

Single-crystal aluminum-gallium oxide films have been grown by molecular beam epitaxy in the corundum phase. Films of the (Al1-xGax)(2)O-3 alloys doped with neodymium have favorable properties for solid-state waveguide lasers, including a high-thermal-conductivity sapphire substrate and a dominant emission peak in the 1090-1096 nm wavelength range. The peak position is linearly correlated to the unit cell volume, which is dependent on film composition and stress. Varying the Ga-Al alloy composition during growth will enable the fabrication of graded-index layers for tunable lasing wavelengths and low scattering losses at the interfaces. (C) 2010 Optical Society of America