Concentration dependence of the fluorescence decay profile in transition metal doped chalcogenide glass

Hughes, MA; Hewak, DW; Curry, RJ

Abstract

In this paper we present the fluorescence decay profiles of vanadium and titanium doped gallium lanthanum sulphide
(GLS) glass at various doping concentrations between 0.01 and 1% (molar). We demonstrate that below a critical doping
concentration the fluorescence decay profile can be fitted with the stretched exponential function: exp[-(t/τ)β], where τ is
the fluorescence lifetime and β is the stretch factor. At low concentrations the lifetime for vanadium and titanium doped
GLS was 30 μs and 67 μs respectively. We validate the use of the stretched exponential model and discuss the possible
microscopic phenomenon it arises from. We also demonstrate that above a critical doping concentration of around 0.1%
(molar) the fluorescence decay profile can be fitted with the double exponential function: a*exp-(t/τ1)+ b*exp-(t/τ2),
where τ1and τ2 are characteristic fast and slow components of the fluorescence decay profile, for vanadium the fast and
slow components are 5 μs and 30 μs respectively and for titanium they are 15 μs and 67 μs respectively. We also show
that the fluorescence lifetime of vanadium and titanium at low concentrations in the oxide rich host gallium lanthanum
oxy-sulphide (GLSO) is 43 μs and 97 μs respectively, which is longer than that in GLS. From this we deduce that
vanadium and titanium fluorescing ions preferentially substitute into high efficiency oxide sites until at a critical
concentration they become saturated and low efficiency sulphide sites start to be filled.

Citation

Hughes, M., Hewak, D., & Curry, R. (2007). Concentration dependence of the fluorescence decay profile in transition metal doped chalcogenide glass. Proceedings of SPIE, 6469, https://doi.org/10.1117/12.699134

• Journal Article Type: Article
• Conference Name: SPIE photonics west
• Start Date: Jan 1, 2007
• Publication Date: Feb 20, 2007
• Deposit Date: Nov 10, 2015
• Journal: Proceedings of SPIE
• Print ISSN: 0277-786X
• Electronic ISSN: 1996-756X
• Publisher: Society of Photo-optical Instrumentation Engineers
• Volume: 6469
• DOI: https://doi.org/10.1117/12.699134
• Publisher URL: http://dx.doi.org/10.1117/12.699134
• Related Public URLs: http://proceedings.spiedigitallibrary.org/ConferenceProceedings.aspx
• Additional Information: Event Type : Conference; Funders : Engineering and Physical Sciences Research Council (EPSRC)