Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods
The luminescence efficiency of Ce3+ in garnet phosphors is among the most stable for luminescent materials. Still, it has been observed to be reduced at high incident blue flux (known as droop) due to nonlinear processes caused by the high lumen density inside the materials. Herein, it is shown that...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Wiley-VCH
2021-08-01
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| Series: | Advanced Photonics Research |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/adpr.202100055 |
| _version_ | 1818620263976140800 |
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| author | Vasilii Khanin Andries Meijerink Arjan J. Houtepen Henri J. B. Jagt Dick K. G. de Boer |
| author_facet | Vasilii Khanin Andries Meijerink Arjan J. Houtepen Henri J. B. Jagt Dick K. G. de Boer |
| author_sort | Vasilii Khanin |
| collection | DOAJ |
| description | The luminescence efficiency of Ce3+ in garnet phosphors is among the most stable for luminescent materials. Still, it has been observed to be reduced at high incident blue flux (known as droop) due to nonlinear processes caused by the high lumen density inside the materials. Herein, it is shown that in the case of Ce3+‐doped garnet concentrator rods, the droop can be explained by excited‐state absorption (ESA) of mainly green Ce3+ luminescence light that is trapped inside the rods. ESA spectroscopy and thermally stimulated luminescence (TSL) measurements show that electrons are promoted from the 5d1 excited state of Ce3+ to the conduction band by ESA and may be either captured by traps or may recombine with Ce4+ sites to give excited Ce3+ ions giving rise to luminescence. Therefore, the droop depends on the concentration of Ce4+ ions present, which can be influenced and optimized by varying the processing conditions of the samples. Guided by these results, a model is developed that describes the optical processes. It is used to analyze the observed droop behavior in block‐shaped samples with and without extraction optics. |
| first_indexed | 2024-12-16T17:50:37Z |
| format | Article |
| id | doaj.art-90ef14e3b023482380e25800058552e4 |
| institution | Directory Open Access Journal |
| issn | 2699-9293 |
| language | English |
| last_indexed | 2024-12-16T17:50:37Z |
| publishDate | 2021-08-01 |
| publisher | Wiley-VCH |
| record_format | Article |
| series | Advanced Photonics Research |
| spelling | doaj.art-90ef14e3b023482380e25800058552e42022-12-21T22:22:19ZengWiley-VCHAdvanced Photonics Research2699-92932021-08-0128n/an/a10.1002/adpr.202100055Photosaturation in Luminescent LuAG:Ce Garnet Concentrator RodsVasilii Khanin0Andries Meijerink1Arjan J. Houtepen2Henri J. B. Jagt3Dick K. G. de Boer4Condensed Matter and Interfaces Debye Institute for Nanomaterials Science Utrecht University Princetonplein 1 3584CC Utrecht The NetherlandsCondensed Matter and Interfaces Debye Institute for Nanomaterials Science Utrecht University Princetonplein 1 3584CC Utrecht The NetherlandsOptoelectronic Materials, Department of Chemical Engineering Delft University of Technology Van der Maasweg 9 2629HZ Delft The NetherlandsSignify Research, Group Light Sources & Materials High Tech Campus 7 5656AE Eindhoven The NetherlandsSignify Research, Group Light Sources & Materials High Tech Campus 7 5656AE Eindhoven The NetherlandsThe luminescence efficiency of Ce3+ in garnet phosphors is among the most stable for luminescent materials. Still, it has been observed to be reduced at high incident blue flux (known as droop) due to nonlinear processes caused by the high lumen density inside the materials. Herein, it is shown that in the case of Ce3+‐doped garnet concentrator rods, the droop can be explained by excited‐state absorption (ESA) of mainly green Ce3+ luminescence light that is trapped inside the rods. ESA spectroscopy and thermally stimulated luminescence (TSL) measurements show that electrons are promoted from the 5d1 excited state of Ce3+ to the conduction band by ESA and may be either captured by traps or may recombine with Ce4+ sites to give excited Ce3+ ions giving rise to luminescence. Therefore, the droop depends on the concentration of Ce4+ ions present, which can be influenced and optimized by varying the processing conditions of the samples. Guided by these results, a model is developed that describes the optical processes. It is used to analyze the observed droop behavior in block‐shaped samples with and without extraction optics.https://doi.org/10.1002/adpr.202100055excited-state absorptiongarnetslight sourcesluminescent materialsphosphor droop |
| spellingShingle | Vasilii Khanin Andries Meijerink Arjan J. Houtepen Henri J. B. Jagt Dick K. G. de Boer Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods Advanced Photonics Research excited-state absorption garnets light sources luminescent materials phosphor droop |
| title | Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods |
| title_full | Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods |
| title_fullStr | Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods |
| title_full_unstemmed | Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods |
| title_short | Photosaturation in Luminescent LuAG:Ce Garnet Concentrator Rods |
| title_sort | photosaturation in luminescent luag ce garnet concentrator rods |
| topic | excited-state absorption garnets light sources luminescent materials phosphor droop |
| url | https://doi.org/10.1002/adpr.202100055 |
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