球壳量子点中极化子和量子比特的声子效应

采用求解能量本征方程、LLP幺正变换、变分相结合的方法研究 球壳量子点中极化子和量子比特的声子效应. 数值计算表明: 声子效应使极化子的基态(或激发态)能量小于电子的基态(或激发态)能量, 使量子比特的振荡周期减小, 且内径给定时, 随着外径的增大声子效应对极化子和量子比特振荡周期的影响越大; 声子效应不改变量子比特内电子概率密度分布的幅值, 量子比特内中心球面处概率密度幅值最大, 界面处概率密度为零, 其它处的概率密度幅值介于最大和最小之间, 且各个空间点的概率密度随半径和方位角的变化而变化, 随时间做周期性振荡.

The phonon effect of polaron and qubit in spherical shell quantum dot

The influence of phonon on the properties of polaron and qubit in spherical shell quantum dot is studied by solving accurately the time-independent Schrödinger equation, Lee-Low-Pines unitary transformation and variation methods. The numerical results indicate that phonon effect leads to a lower energy of ground (or excited) state of polaron than electronic energy of ground (or excited) state and the increased oscillating period of a qubit, and the phonon effect becomes more obvious with outer radius increasing when inner radius is const. The numerical results also show that the phonon effect cannot influence the amplitude of probability density distribution of electrons in quantum bit, and that the probability density distribution of electrons is dependent on co-ordinate and time and its amplitude is maximal in centre spherical surface and but zero in boundary surface. The probability density of electrons at each position oscillates periodically with time.