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Title: Spectroscopic study of Er-doped Ga 2 Ge 5 S 13 glass for mid-IR laser applications

We present mid-IR spectroscopic characterization of the low-phonon chalcogenide glass, Ga2Ge5S13(GGS) doped with Er3+ions. Under the excitation at ∼800 nm, Er3+:GGS exhibited broad mid-IR emission bands centered at ∼2.7, ∼3.5, and ∼4.5 µm at room temperature. The emission lifetime of the4I9/2level of Er3+ions in GGS glass was found to be millisecond-long at room temperature. The measured fluorescence lifetimes were nearly independent of temperature, indicating negligibly small nonradiative decay rate for the4I9/2state, as can be expected for a low-maximum-phonon energy host. The transition line-strengths, radiative lifetimes, fluorescence branching ratios were calculated by using the Judd-Ofelt method. The peak stimulated emission cross-section of the4I9/24I11/2transition of Er3+ion was determined to be ∼0.10×10−20cm2at room temperature.

 
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NSF-PAR ID:
10369527
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optical Materials Express
Volume:
12
Issue:
4
ISSN:
2159-3930
Page Range / eLocation ID:
Article No. 1627
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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