Fabrication and characterization of nanoscale, Er3+-doped, ultratransparent oxy-fluoride glass ceramics

Publisher Website
Google Scholar
Abstract
We show that oxy-fluoride glass ceramics, with typical composition, 32( SiO 2 ):9( AlO 1.5 ):31.5( CdF 2 ):18.5( PbF 2 ):5.5( ZnF 2 ): 3.5( ErF 3 ) mol % have potential applications in telecommunications. Upon heat treatment, Er 3+ nucleates the growth of the nanocrystalline β- PbF 2 , which acts as its host. Heat treatment at 440 ° C for 5 h and at 390 ° C for 3 h gave rise to ∼12 and ∼2.5 nm diameter crystals, respectively. The emission band of Er 3+ in the 1.54 μm telecommunications window ( 4 I 13/2 → 4 I 15/2 transition, at the half-height width) was 75 nm in the former and 90 nm in the latter case, while 4 I 13/2 ↔ 4 I 15/2 absorption and emission bands became wavelength divergent in both cases. Also in the latter case, the spectrum was flat from 1.53 to 1.56 μm. The evolution of spectral behavior is explained by changes in average site geometry of the Er 3+ dopant, related to the α→β phase transition of PbF 2 , which is stimulated by heat treatment.