声子色散对量子点中磁极化子性质的影响:压缩态变分法

采用基于逐次正则变换的变分方法研究了利用单模压缩态变换处理双线性项的情况下声子色散对抛物量子点中磁极化子性质的影响。首先,应用位移振子形式的幺正变换来对角化相关的哈密顿量,然后采用压缩态变换来处理在第一次幺正变换中产生的双线性项。计算了在声子色散影响下磁极化子的基态能量及电子周围平均声子数。讨论了在弱耦合情况下,受限长度、回旋频率、电子-声子耦合常数、色散系数分别与基态能量和平均声子数之间的依赖关系。我们可以得到基态能量随受限长度的减小和回旋频率的增加而迅速增大,随着色散系数的增大而降低,平均声子数随着色散系数的增大而减小。

Influence of Phonon Dispersion on the Properties of Magnetopolaron in a Quantum Dot:Squeezed-state Variational Approach

By applying a variational approach based on two successive canonical transformations and using a displaced-oscillator type unitary transformation to deal with bilinear terms,the influence of the dispersion of phonon on properties of magnetopolaron in a parabolic quantum dot(QD)is studied.The ground state energy and the average number of virtual phonons around the electron of weak-coupling magnetopolaron are calculated considering the in-fluence of the dispersion of phonon.Their dependence on the confinement length,the cyclotron frequency,the electron-LO-phonon coupling constant and the coefficient of phonon dispersion is depicted in the electron-LO-phonon weak-coupling case.