title: Near-infrared to mid-infrared photoluminescence of Bi2O3-GeO2 binary glasses: comment.
abstract: We discuss the origin of near- to mid-infrared emissions in Bi-doped oxide glasses recently reported [Opt. Lett.37, 4260 (2012)]. Our detailed analysis indicates that the near- to mid-infrared emissions in the range of 1200-3000 nm peaking at ~2500, 2650, and 2700 nm do not result from Bi active centers in the oxide matrix but are due to the selective atmospheric absorption of thermal radiation induced by laser irradiation.
authors.affiliation: State Key Laboratory of Luminescent Materials and Devices and Institute of Optical Communication Materials, South China University of Technology, Guangzhou 510640, China.
authors.forename: Renping
authors.initials: R
authors.lastname: Cao
authors.forename: Fangteng
authors.initials: F
authors.lastname: Zhang
authors.forename: Guoping
authors.initials: G
authors.lastname: Dong
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.forename: Jianrong
authors.initials: J
authors.lastname: Qiu