Synthesis and Optical Properties of Rare‐Earth–Aluminum Oxide Glasses

Abstract

Single-phase glasses containing 37.5 mol% Y 2 O 3 , 7 mol% La 2 O 3 , and 1 mol% Pr, Ho, Nd, Er, Sm, Tm, Eu, or Yb oxide substituted for part of the Y 2 O 3 were synthesized by containerless melting. The spectral transmission and absorption cross sections of the glasses were determined at wavelengths from 360 to 3300 nm. The electronic transitions were broadened compared with results obtained in a crystalline yttrium aluminum garnet (YAG) host. The infrared transmission of the host glass extended to 6000 nm. The optical and physicochemical properties of these glasses are well suited for optical device applications. † Balance is Al 2 O 3 in all cases. ‡ Equivalent to 3.1 ϫ 10 20 Re 3ϩ ions/cm 3 . § Two-phase glass.

Rare earth–aluminum oxide glasses for optical applications

“…Addition of 20 mol% silica had no measurable effect o the dissolution rate in water. The silica-free glass compositions resisted attack by concentrated aqueous hydrofluoric acid [8]; this acid fogged the surface of the silica-containing glass after a few hours exposure.…”

“…Properties measured were density, hardness, glass transition temperature, crystallization temperature, corrosion resistance, index of refraction, infrared transmission, ground-state absorption cross section [8] and fluorescence behavior of optically active ions.…”

“…These were prepared by mounting glass in 25 mm diameter, 3 mm thick epoxy resin mounts and plane polishing them on two surfaces to form nearlyparallel disks 1-2.5 mm thick [8]. The surfaces were polished to a 0.05 lm finish using water-based alumina slurry.…”

“…Phosphate [3][4][5], tellurite [6] and aluminosilicate glass materials [1,8] can dissolve relatively large concentrations of dopants compared to pure silica glasses. At higher dopant concentrations, >500 ppm, ÔclusteringÕ of dopant ions in silicate glasses leads to energy transfer processes that decrease device efficiency [2].…”

Thermal and mechanical properties of rare earth aluminate and low-silica aluminosilicate optical glasses

“…At higher dopant concentrations, >500 ppm, Ôclus-teringÕ of dopant ions leads to energy transfer processes that decrease device efficiency [2]. Phosphate [3][4][5], tellurite [6], and aluminosilicate glass materials [1,8] can dissolve relatively large concentrations of dopants compared to pure silica glasses. The high phonon energies of phosphates and silicates limits their use to visible and near infrared applications.…”