Abstract
Erbium doped silicon-rich silica offers broad band and very efficient excitation of erbium photoluminescence (PL) due to a sensitization effect attributed to silicon nanocrystals (Si-nc), which grow during thermal treatment. PL decay lifetime measurements of sensitised Er 3 ions are usually reported to be stretched or multi exponential, very different to those that are directly excited, which usually show a single exponential decay component. In this paper, we report on SiO 2 thin films doped with Si-ncs and erbium. Time resolved PL measurements reveal two distinct 1.54 μm Er decay components; a fast microsecond component, and a relatively long lifetime component (10 ms). We also study the structural properties of these samples through TEM measurements, and reveal the formation of Er clusters. We propose that these Er clusters are responsible for the fast μs decay component, and we develop rate equation models that reproduce the experimental transient observations, and can explain some of the reported transient behaviour in previously published literature. © 2012 Elsevier B.V.
Original language | English |
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Pages (from-to) | 3103-3112 |
Number of pages | 9 |
Journal | Journal of Luminescence |
Volume | 132 |
Issue number | 12 |
DOIs | |
Publication status | Published - Dec 2012 |
Keywords
- Energy migration
- Erbium cluster
- Ion-ion interactions
- Lifetimes
- Rate equations
- Si-nanocrystal