Xuan Zhang, Jingyi Liu, Jiapan Zheng, Hao Wu, Ruiqing Gong, Jiaru Wang, Zixuan Song, Honghao Xu, Yuxia Zhang and Junhai Liu
{"title":"Dy,Tb:CaWO4晶体的单晶生长及冷白光应用","authors":"Xuan Zhang, Jingyi Liu, Jiapan Zheng, Hao Wu, Ruiqing Gong, Jiaru Wang, Zixuan Song, Honghao Xu, Yuxia Zhang and Junhai Liu","doi":"10.1039/D5CE00186B","DOIUrl":null,"url":null,"abstract":"<p >We report the Dy:CaWO<small><sub>4</sub></small> and Dy,Tb:CaWO<small><sub>4</sub></small> crystals grown by the Czochralski method, and their structural and optical properties are studied. Raman spectra, polarization absorption spectra, polarization emission spectra, and fluorescence lifetime are obtained. The Judd–Ofelt intensity parameters (<em>Ω</em><small><sub><em>t</em></sub></small>, <em>t</em> = 2, 4, 6), the fluorescence branching ratios, and the radiative lifetimes of the <small><sup>4</sup></small>F<small><sub>9/2</sub></small> level are calculated based on the Judd–Ofelt theory. The emission cross-sections are calculated using the Füchtbauer–Ladenburg method, showing large emission cross-sections at 573 nm: 9.86 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (π polarization) and 8.11 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (σ polarization) for Dy:CaWO<small><sub>4</sub></small>, and 9.09 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (π polarization) and 7.69 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (σ polarization) for Dy,Tb:CaWO<small><sub>4</sub></small>, respectively. In addition, under 450 nm excitation, the crystals emit ideal white light, with CIE coordinates (0.3258, 0.3191) and a correlated color temperature of 6000 K. Therefore, Dy:CaWO<small><sub>4</sub></small> and Dy,Tb:CaWO<small><sub>4</sub></small> crystals are promising materials for white light-emitting diode (LED) applications.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 17","pages":" 2672-2682"},"PeriodicalIF":2.6000,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Single crystal growth and cold white light application of Dy,Tb:CaWO4 crystals\",\"authors\":\"Xuan Zhang, Jingyi Liu, Jiapan Zheng, Hao Wu, Ruiqing Gong, Jiaru Wang, Zixuan Song, Honghao Xu, Yuxia Zhang and Junhai Liu\",\"doi\":\"10.1039/D5CE00186B\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >We report the Dy:CaWO<small><sub>4</sub></small> and Dy,Tb:CaWO<small><sub>4</sub></small> crystals grown by the Czochralski method, and their structural and optical properties are studied. Raman spectra, polarization absorption spectra, polarization emission spectra, and fluorescence lifetime are obtained. The Judd–Ofelt intensity parameters (<em>Ω</em><small><sub><em>t</em></sub></small>, <em>t</em> = 2, 4, 6), the fluorescence branching ratios, and the radiative lifetimes of the <small><sup>4</sup></small>F<small><sub>9/2</sub></small> level are calculated based on the Judd–Ofelt theory. The emission cross-sections are calculated using the Füchtbauer–Ladenburg method, showing large emission cross-sections at 573 nm: 9.86 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (π polarization) and 8.11 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (σ polarization) for Dy:CaWO<small><sub>4</sub></small>, and 9.09 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (π polarization) and 7.69 × 10<small><sup>−21</sup></small> cm<small><sup>2</sup></small> (σ polarization) for Dy,Tb:CaWO<small><sub>4</sub></small>, respectively. In addition, under 450 nm excitation, the crystals emit ideal white light, with CIE coordinates (0.3258, 0.3191) and a correlated color temperature of 6000 K. Therefore, Dy:CaWO<small><sub>4</sub></small> and Dy,Tb:CaWO<small><sub>4</sub></small> crystals are promising materials for white light-emitting diode (LED) applications.</p>\",\"PeriodicalId\":70,\"journal\":{\"name\":\"CrystEngComm\",\"volume\":\" 17\",\"pages\":\" 2672-2682\"},\"PeriodicalIF\":2.6000,\"publicationDate\":\"2025-03-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"CrystEngComm\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://pubs.rsc.org/en/content/articlelanding/2025/ce/d5ce00186b\",\"RegionNum\":3,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"CrystEngComm","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2025/ce/d5ce00186b","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
Single crystal growth and cold white light application of Dy,Tb:CaWO4 crystals
We report the Dy:CaWO4 and Dy,Tb:CaWO4 crystals grown by the Czochralski method, and their structural and optical properties are studied. Raman spectra, polarization absorption spectra, polarization emission spectra, and fluorescence lifetime are obtained. The Judd–Ofelt intensity parameters (Ωt, t = 2, 4, 6), the fluorescence branching ratios, and the radiative lifetimes of the 4F9/2 level are calculated based on the Judd–Ofelt theory. The emission cross-sections are calculated using the Füchtbauer–Ladenburg method, showing large emission cross-sections at 573 nm: 9.86 × 10−21 cm2 (π polarization) and 8.11 × 10−21 cm2 (σ polarization) for Dy:CaWO4, and 9.09 × 10−21 cm2 (π polarization) and 7.69 × 10−21 cm2 (σ polarization) for Dy,Tb:CaWO4, respectively. In addition, under 450 nm excitation, the crystals emit ideal white light, with CIE coordinates (0.3258, 0.3191) and a correlated color temperature of 6000 K. Therefore, Dy:CaWO4 and Dy,Tb:CaWO4 crystals are promising materials for white light-emitting diode (LED) applications.