高聚物中极化子和三重态激子的碰撞过程研究  

Study on the process of collision between a polaron and a triplet exciton in conjugated polymers

作　　者：孙震[1] 安忠[2] 李元[1] 刘文[1] 刘德胜[1,3] 解士杰[1] 

机构地区：[1]山东大学物理学院,晶体材料国家重点实验室,济南250100 [2]河北师范大学物理科学与信息工程学院,石家庄050016 [3]山东济宁学院物理系,曲阜273155

出　　处：《物理学报》2009年第6期4150-4155,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10574082;10574037);山东省自然科学基金(批准号:Z2005A01);教育部新世纪优秀人才支持计划(批准号:NCET-05-0262)资助的课题~~

摘　　要：采用一维紧束缚近似的SSH模型,计算了不同强度的电场下高聚物中一个负电极化子和一个三重态激子的碰撞过程.结果表明,碰撞后体系仍保持为极化子和三重态激子状态的几率最大,束缚在极化子缺陷中的电子有较大的几率被激发到导带形成自由电子,另外,三重态激子有一定的几率被极化子湮灭形成极化子激发态.极化子和激子的碰撞对极化子的稳定性有影响,还会使能隙中出现新的能级.由于极化子激发态可以通过辐射跃迁回到基态,因此碰撞会对高聚物的电致发光效率产生一定影响.研究结果对于理解高聚物中极化子的输运性质和高聚物的发光性质具有一定的帮助.Adopting a tight-binding electron-phonon interacting model, we investigated the collision between a negative polaron and a triplet exciton in polymers under the influence of different electric fields. The results show that, after the collision, the electrons of the system have the most probability of keeping the same configuration as it initially is. The electron confined in the polaron defect has some probabilities to be excited into the conduction band to form a free carrier, and the triplet exciton has some, even less, probabilities to be annihilated by the negative polaron to form an excited polaron in the collision. It is also found that the collision proccess can influence the stability of the polaron and there are new energy levels appearing in the gap after the collision. Because an excited polaron can decay radiatively to its ground state, the scattering process has influence on the efficiency of electroluminescence. These results will help us to understand the properties of polaron transport and electroluminescence in polymers.

关 键 词：极化子 激子 高聚物 

分 类 号：O631.1[理学—高分子化学]