Abstract: This invention relates to the use of novel glass materials comprising rare earth aluminate glasses (REA1™ glasses) in the gain medium of solid state laser devices that produce light at infrared wavelengths, typically in the range 1000 to 3000 nm and for infrared optics with transmission to approximately 5000 nm in thin sections. The novel glass materials provide stable hosts for trivalent ytterbium (Yb3+) ions and other optically active species or combinations of optically active species that exhibit fluorescence and that can be optically excited by the application of light. The glass gain medium can be configured as a waveguide or placed in an external laser cavity, or otherwise arranged to achieve gain in the laser waveband and so produce laser action.

Abstract: The present invention provides a method for drawing fibers from materials which exhibit low viscosities at the equilibrium melting temperature. Further, the present invention provides novel drawn fibers from materials which were thought to be incompatible with a fiber-drawing process. The present invention also provides a means of minimizing recrystallization of molten materials during fiber drawing. Still further, the present invention provides novel drawn fibers with a greater tensile strength and greater concentrations of additives as compared to prior art fibers. Lastly, the present invention provides a means for producing crystalline fibers with controlled chemical compositions, and fibers with high tensile strengths as compared to prior art fibers of the same composition.

Abstract: A bulk single phase glass comprising 23 molar % to 50 molar % rare earth oxides, RE203, and 50 molar % to 77 molar % aluminum oxide, A12O3 is provided. The glass contains at least 50 molar % of Al2O3+RE2O3 and smaller amounts of oxide glass forming agents and other oxides than are found in prior art glasses. The addition of small amounts of lanthanum oxide, La2O3, prevents phase separation. The single phase glass is useful for optical applications such as lasers and optical amplifiers.