三种状态蒽的三重态吸收性质研究  

Study on the Triplet State Absorption Properties of Three States of Anthracene

作　　者：周庆 陈昕昕 谢俊涵 张力[1,2] 孙静 王中阳 ZHOU Qing;CHEN Xinxin;XIE Junhan;ZHANG Li;SUN Jing;WANG Zhongyang(Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201210,CHN;University of Chinese Academy of Sciences,Beijing 100049,CHN;School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,CHN)

机构地区：[1]中国科学院上海高等研究院,上海201210 [2]中国科学院大学,北京100049 [3]上海科技大学物质科学与技术学院,上海201210

出　　处：《半导体光电》2023年第6期863-868,共6页Semiconductor Optoelectronics

基　　金：上海市科学技术委员会项目(20DZ2210300).

摘　　要：利用瞬态吸收光谱技术研究了蒽在甲苯溶液和PMMA薄膜及晶体中的瞬态吸收过程,发现当激发波长375 nm处的吸收度为0.7时,溶液中蒽的三重态最大吸收信号强度为其在PMMA中的5倍,而在高吸收度的晶体中,三重态吸收较低。通过建立模型分析,PMMA中的蒽分子存在光场诱导下偶极矩的宏观统计极化,导致宏观极化偶极矩的降低,而处于甲苯溶液中的蒽分子则易被光场所极化,产生较大的极化偶极矩,这是引起三重态吸收信号差异的原因。在晶体状态下,S_(1)能级发生分裂,低于T_(2)能级,S_(1)-T_(1)能量差较大,系间窜越失效,抑制了三重态吸收。以上结果解释了蒽分子在不同状态下三重态最大吸收信号差异。The transient absorption process of anthracene in toluene solution,PMMA film and crystal was studied by transient absorption spectroscopy.It was found that when the absorption was 0.7 at the excitation wavelength of 375nm,the maximum absorption signal intensity of the triplet state of anthracene in solution was five times that in PMMA.In the crystal with high absorption,the triplet state absorption signal was lower.By establishing a model,it was found that the anthracene molecules in PMMA exhibited macroscopic statistical polarization of the induced dipole moment under the optical field,resulting in a decrease in macroscopic polarization dipole moments.On the other hand,the anthracene molecules in the toluene solution were easily polarized by the optical field,resulting in a larger polarized dipole moment.This is the reason for the difference in triplet state absorption signals.In the crystal state,the S_(1) energy level splits and is lower than T_(2).The energy gap between S_(1) and T_(1) is large,and the intersystem crossing is not effective,which inhibits the absorption of the triplet state.These results explain the difference in the maximum absorption signal of the triplet state of anthracene in different states.

关 键 词：蒽 三重态 瞬态吸收光谱 超快动力学 

分 类 号：O411.3[理学—理论物理]