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Updated: Mar 9, 2026
07:24
Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
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Consequences of Ca Codoping in YAlO3 :Ce Single Crystals
Federico Moretti1,2, Karine Hovhannesyan3, Marina Derdzyan3
1Institut Lumière Matière, UMR55306 Université Claude Bernard Lyon 1-CNRS, Bâtiment Kastler, 10 rue Ada Byron, 69622, Villeurbanne CEDEX, France.
Summary
Calcium codoping in YAlO3:Ce crystals improves timing performance for applications but reduces scintillation efficiency due to Ce4+ ion formation. This study investigates optical and luminescence properties under varying Ca concentrations.
Area of Science:
- Materials Science
- Solid State Physics
- Luminescence
Background:
- Yttrium aluminum perovskite doped with cerium (YAP:Ce) is a scintillator material.
- Understanding dopant effects is crucial for optimizing scintillator performance.
- Calcium (Ca) codoping is explored to modify YAP:Ce properties.
Purpose of the Study:
- To investigate the impact of Ca codoping on YAP:Ce crystals.
- To analyze changes in optical absorption and luminescence properties.
- To evaluate the effect of Ca on scintillation timing and efficiency.
Main Methods:
- Synthesis of YAP:Ce crystals with varying Ca concentrations (0–500 ppm).
- Optical absorption spectroscopy.
- Photo-, radio-, and thermo-luminescence measurements.
- Pulsed X-ray excitation to study luminescence time response.
Main Results:
- Ca codoping leads to partial oxidation of Ce3+ to Ce4+ ions.
- Hole migration significantly influences luminescence rise time and slow components.
- Improved timing characteristics observed with Ca codoping.
- Scintillation efficiency is reduced due to the presence of Ce4+.
Conclusions:
- Ca codoping offers a trade-off between improved timing and reduced efficiency in YAP:Ce scintillators.
- The formation of Ce4+ and associated hole migration are key mechanisms.
- Careful control of Ca concentration is necessary for specific applications.
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