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Updated: Jun 3, 2026
11:30
Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
Recombination processes in systems based on doped ionic crystals with impurity-related nanostructures
D O Tolmachev1, A G Badalyan, R A Babunts
1Ioffe Physical-Technical Institute, Russian Academy of Sciences, St Petersburg, Russia.
Summary
Energy transfer in X-ray storage phosphors was studied. Spin-dependent recombination in CsBr:Eu and CsBr:Pb crystals directs energy to impurity nanostructures, crucial for luminescence.
Area of Science:
- Solid State Physics
- Materials Science
- Luminescence
Background:
- Ionic crystals with impurity nanostructures are promising phosphors for X-ray storage.
- Understanding recombination processes is key to optimizing phosphor performance.
Purpose of the Study:
- To investigate recombination mechanisms in X-ray irradiated CsBr:Eu and CsBr:Pb crystals.
- To elucidate the energy transfer pathways from the host crystal to impurity nanostructures.
Main Methods:
- Luminescence spectroscopy
- Electron Paramagnetic Resonance (EPR)
- Optically Detected Magnetic Resonance (ODMR)
Main Results:
- Spin-dependent tunneling recombination of electron-hole pairs and self-trapped excitons was observed.
- Energy released during recombination is directionally transferred to impurity-related low-dimensional structures.
- EPR spectra of recombining centers were identified by monitoring luminescence.
Conclusions:
- The study clarifies energy transfer mechanisms in X-ray storage phosphors.
- Identified recombination centers provide insights for designing improved phosphors.
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