量子点量子阱结构中极化子效应对斯塔克能移的影响(英文)

Polaronic Effect on the Stark Shift in a Quantum Dot Quantum Well Structure

采用变分法研究了量子点量子阱结构中极化子效应对斯塔克能移的影响.计算中考虑了电子与体纵光学声子和表面光学声子的相互作用.以CdS/HgS量子点量子阱结构为例进行数值计算,发现极化子基态能量随量子点半径的增加而单调增加,随电场强度的增加而单调减少.电子-声子相互作用增强了斯塔克能移.极化子自陷能随量子点半径及电场强度的增加而增加.量子点量子阱结构的尺寸对极化子斯塔克能移有显著影响.

The polaronic effect on the Stark shift in a quantum dot quantum well structure is studied theoretically by using a variational approach. The interactions of an electron with both the longitudinal optical phonons and the surface optical phonons are taken into account in the framework of the dielectric continuum approximation. The calculations are carried out for a CdS/HgS quantum dot quantum well structure. The numerical results show that the ground-state energy of the polaron increases monotonously with increasing the core radius, hut decreases with increasing the electric field intensity. The electron-phonon interaction enhances the Stark shifts. The self-trapping energy of the polaron increases when the electric field intensity and the core radius increase, respective- ly. The size of a quantum dot quantum well structure gives a significant influence on Stark shifts of polarons.