极化子效应对ZnS/CdSe量子点三阶极化率的影响  

Effect of Polaron Effect on Third-order Susceptibility in ZnS/CdSe Quantum Dot Quantum Well

作　　者：陈知红[1] 王军延[1] 方天红[1] 

机构地区：[1]孝感学院物理与电子信息工程学院,湖北孝感432000

出　　处：《发光学报》2009年第4期535-540,共6页Chinese Journal of Luminescence

基　　金：湖北省孝感学院科学研究项目(Z2010008)资助

摘　　要：在有效质量近似下,利用量子力学的密度矩阵理论,采用无限深势阱模型,从理论上计算了考虑极化子效应后在导带子带间跃迁时ZnS/CdSe柱型核壳结构量子点二次电光效应(QEOE)和电吸收过程(EA)的三阶极化率。通过数值计算,分析了电子-LO声子和电子-IO声子相互作用对ZnS/CdSe柱型核壳结构量子点二次电光效应和电吸收过程的三阶极化率的影响。结果表明,极化子效应对二次电光效应的三阶极化率χQEDE(3)和电吸收过程的三阶极化率χE(3A)都有很大影响,并且影响的大小与量子点的尺寸大小有关。The effect of the electron-phonon interaction on the quadratic electro-optic effect （QEOE） and electro-absorption process （EA） was investigated theoretically for electrons confined in a core-shell quantum dot. The interactions of electrons with different phonon modes in the core-shell system, including the confined longitudinal optical （LO） and the interface optical （IO）phonon modes, were investigated. We carried out a detailed calculation of quadratic electro-optic effects （QEOE）and electro-absorption process （EA） on a ZnS/ CdSe core-shell quantum dot as a function of pump photon energy with different incident photon energy and under different quantum dot size. The results revealed that the polaron effects are quite important especially around the peak value of the third-order susceptibility.

关 键 词：非线性光学 三阶极化率 极化子效应 二次电光效应 电吸收过程 

分 类 号：O437[机械工程—光学工程] O472.3[理学—光学]