Abstract: A planar waveguide and a process for making a planar waveguide is disclosed. The waveguide has a layer of dope host material formed on a substrate. The host material is a trivalent material such as a metal fluoride, wherein the metal is selected from the Group III B metals and the lanthanide series rare earth metals of the Mendeleevian Periodic Table. The dopant is a rare earth metal such as erbium. The waveguide has an emission spectrum with a bandwidth of about 60 nm for amplification of an optical signal at a wavelength of about 1.51 .mu.m to about 1.57 .mu.m. The waveguide is made by forming the layer of doped host material on a substrate. The film is formed by evaporating materials from two separate sources, one source for the dopant material and a separate source for the host material and forming a film of the evaporated materials on a substrate.

Abstract: A planar waveguide and a process for making a planar waveguide is disclosed. The waveguide has a layer of doped host material formed on a substrate. The host material is a trivalent material such as a metal fluoride, wherein the metal is selected from the Group III B metals and the lanthanide series rare earth metals of the Mendeleevian Periodic Table. The dopant is a rare earth metal such as erbium. The waveguide has an emission spectrum with a bandwidth of about 60 nm for amplification of an optical signal at a wavelength of about 1.51 .mu.m to about 1.57 .mu.m. The waveguide is made by forming the layer of doped host material on a substrate. The film is formed by evaporating materials from two separate sources, one source for the dopant material and a separate source for the host material and forming a film of the evaporated materials on a substrate.