半导体量子点中杂质结合能的理论研究

利用一维有限差分法,计算了一个圆柱形量子点中杂质基态的结合能,研究了电场、磁场和杂质位置对结合能的影响.当杂质位于量子点中心时,结合能随着电场和有效半径的增加而减小;当杂质位于过量子点中心且垂直于轴线的平面上时,结合能随杂质位置远离中心的变化呈对称变化;当杂质位于z轴上时,在电场的作用下这种对称性消失.

Theoretical Study on the Binding Energy of Hydrogenic Impurities in a Semiconductor Quantum Dot

The binding energy of hydrogenic impurities in a cylindrical quantum dot was calculated with the one-dimensional finite-difference method. The effects of the electric field, magnetic field and position of an impurity on the binding energy were studied. When the impurity is located at the center of the quantum dot, the binding energy decreases with increasing electric field and effective radius, and when the impurity is located at the plane normal to the z axis and through the center of the quantum dot, the binding energy changes symmetrically with increasing distance away from the center of the quantum dot. However, when the impurity is located on the z axis, the symmetry vanishes because of the effect of the electric field.