High-excited-state splitting and multimode vibrational coupling in Mn^(4+)-activated fluoride phosphor  

作　　者：Debao Zhang Wanggui Ye Xuguang Cao Ji Zhou Fei Tang Changcheng Zheng Jiqiang Ning Shijie Xu 

机构地区：[1]Department of Optical Science and Engineering,School of Information Science and Technology,Fudan University Shanghai 200438,China [2]Jiangsu Key Laboratory of Advanced Laser Materials and Devices,Schoolof Physics and Electronic Engineering Jiangsu Normal University,Xuzhou 221116,China [3]Division of Natural and Applied Sciences,Duke Kunshan University,Kunshan 215316,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2024年第3期95-101,共7页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 12074324, and 11374247);the Science, Technology, and Innovation Commission of Shenzhen Municipality (Grant Nos. JCJY20180508163404043, and JCYJ20170818141709893)。

摘　　要：Excited-states play a crucial role in the optical absorption and luminescence of solids and hence their accurate information is highly desired. Herein, we attempt to seize the excited-states information of Mn^(4+)ions in K_(2)SiF_(6) microcrystals via measuring and calculating their variable-temperature photoluminescence excitation(PLE) spectra. At cryogenic temperatures, an unpredicted splitting of the high-excited-state is observed. Moreover, the two-split high-excited-state levels are further revealed to primarily couple with the two hyperfine split modes of quasi-localized ν2 vibration in the distorted Mn-F_(6) octahedral configuration,whereas the coupling strengths are found to be substantially different from each other. The slightly split vibrational mode is firmly supported by the low-temperature Raman spectra. Jahn-Teller lattice distortion is believed to be responsible for the observed splitting of the electronic high-excited-state and the quasi-localized vibrational mode.

关 键 词：splitting of excited-state photoluminescence excitation spectrum electron-phonon coupling Jahn-Teller effect 

分 类 号：TQ422[化学工程]