非对称量子点中强耦合束缚极化子的性质

Properties of Strong-coupling Bound Polaron in an Asymmetric Quantum Dot

采用线性组合算符和幺正变换方法研究库仑场对非对称量子点中强耦合极化子性质的影响。导出了非对称量子点中强耦合束缚极化子的振动频率、基态能量和基态结合能随量子点的横向和纵向有效受限长度,库仑束缚势和电子-声子耦合强度的变化关系。数值计算结果表明:非对称量子点中强耦合束缚极化子的振动频率、基态能量和基态结合能随量子点的横向和纵向有效受限长度的减小而迅速增大,表现出新奇的量子点的量子尺寸效应。基态能量随库仑束缚势和电子-声子耦合强度的增加而减小,振动频率和基态结合能随电子-声子耦合强度和库仑束缚势的增加而增大。

The influences of Coulomb field on the properties of strong-coupling polaron in an asymmetric quantum dot are studied by using the linear combination operator and the unitary transformation methods. The relations of the vibrational frequency, the ground state energy and the ground state binding energy of strong-coupling bound polaron in an asymmetric quantum dot with the transverse and the longitudinal effective confinement length of quantum dot, the Coulomb bound potential and the electron-phonon coupling strength were derived. Numerical calculations are performed and the results show that the vibrational frequency, the ground state energy and the ground state binding energy of strong-coupling bound polaron in an asymmetric quantum dot will increase strongly with decreasing the transverse and the longitudinal effective confinement length of quantum dot, and the ground state energy will increase with decreasing the Coulomb bound potential and the electron-phonon coupling strength. The vibrational frequency and the ground state binding energy will increase with increasing the electron-phonon coupling strength and the Coulomb bound potential.