量子阱中极化子的声子平均数  

Mean Number of Phonons of Polaron in Quantum Well

作　　者：刘伟华[1] 肖景林[1] 

机构地区：[1]内蒙古民族大学物理与机电学院,内蒙古通辽028043

出　　处：《发光学报》2005年第5期575-580,共6页Chinese Journal of Luminescence

基　　金：国家自然科学基金资助项目(10347004)

摘　　要：采用有效质量近似下的变分法,考虑到电子同时与表面光学声子和体纵光学声子相互作用,研究了无限深量子阱中极化子的表面光学声子平均数,体纵光学声子平均数和光学声子平均数。讨论了电子与体纵光学声子耦合强度α,阱宽L和势垒材料A lxGa1-xAs中A l的含量x对上述光学声子平均数的影响。以GaAs/A lxGa1-xAs量子阱为例进行了数值计算。结果表明:量子阱中表面光学声子平均数随耦合强度α,阱宽L和A l含量x增大而增大。量子阱中体纵光学声子平均数随耦合强度α,阱宽L的增大而增大。光学声子平均数随耦合强度α,阱宽L和A l含量x的增大而增大。With the technological progress in material growth, semiconductor quantum wells and heterostructures were obtained experimentally. There has been considerable interest in physical properties of low-dimensional material. Using perturbation method, Hai studied the energy and effective mass of polaron in Q2D system, in calculation, the interface phonon, 3D bulk phonon mode, parabolic quantum wells , infinite and finite quantum wells have been taken into account. Zheng studied the ground state energy and effective mass of a Q2D polaron system in a Qw by using a modified Lee-Low-Pines transformation. Mori and Ando obtained that the effects for electron and different phonon mode interaction have the same result as bulk phonon mode. Employing second order perturbation theory, intermediate coupling theory and interpolation formula, Sarma discussed the influence of electron-LO phonon interaction on the electronic properties of single two dimensional electronic slab. By using the standard perturbation theory within the Thomas-Fermi approximation, Comas and Racker calculated self-energy of weak coupling laron in a finite and infinite QW by means of polaron. Li investigated the Stark energy shifts of a bound poperturbation-variation method. Ren carried out the FeynmanHaken path integral theory to calculated the ground state energy of polaron in parabolic quantum well. Eerdun studied the temperature dependence of properties of electron-bulk LO phonon interaction system in a quantum well within the electronic-magnetic fields along the growth axis by means of variational wave-function and harmonic oscillator algebra method and he also obtained the self-energy of the system at a finite temperature. Although the properties of polaron in QW were studied by many methods, the study about the mean number of polaron in QW are seldom investigated. The properties of polaron in infinite quantum well were studied by using variational method within the effective-mass approximation. Numerical calculations, taking GaAs/ AI^Ga1_~As quantum w

关 键 词：量子阱 变分法 声子平均数 

分 类 号：O469[理学—凝聚态物理] O482.3[理学—电子物理学]