在考虑电子与体纵光学声子强耦合的条件下,通过求解能量本征方程,得出了盘型量子点中电子的基态能量、第一激发态能量及其相应的本征波函数;采用幺正变换和元激发理论方法研究了圆盘型量子点的声子效应,并讨论了温度对量子盘中极化子性质的影响。数值计算表明:在温度较低时,声子不能被激发,温度对能量无影响,当温度较高时,声子能够被激发,且温度愈高,被激发的声子数愈多,极化子能量愈大;结果还表明基态能量随着电子-声子耦合强度的增大而减小,随量子盘半径的增大而减小,说明量子盘具有明显的量子尺寸效应。
Under the condition of electron-LO-phonon strong coupling, the eigen-energy and corresponding eigen-wave functions of the ground state and first excited state of electron in quantum disk were obtained by solving the energy eigen-equation precisely. The phonon effect and temperature effect were studied by unitary transformation and elementary excitation theory method. Furthermore, the temperature effect on the ground energy of the polaron in quantum disk was also discussed. Numerical results showed that few phonons were excited at low temperature, while in the condition of high temperature, the energy of polaron was effected by temperature, and the higher temperature, the more phonons. The results also indicated that the energy of the ground state of polaron decreased with the increasing electron-LO phonon coupling strength. It means that quantum disk has obvious quantum size effect.