量子棒中弱耦合极化子有效质量的温度依赖性

Temperature Dependence of Effective Mass of Weak-Coupling Polaron in a Quantum Rod

基于Tokuda-Lee-Low-Pines变分法研究了温度对非均匀抛物限制势下量子棒中弱耦合极化子有效质量的影响,推导出量子棒中弱耦合极化子的有效质量m*随量子棒纵横比e′、电子-声子耦合强度α和温度参数γ的变化规律。数值计算结果表明,量子棒中弱耦合极化子的横向有效质量m‖*和纵向有效质量mz*均随电子-声子耦合强度α的增加而增大,随温度T的升高而减小;量子棒中极化子的横向有效质量m‖*随量子棒纵横比e′的增加而增大,纵向有效质量mz*随e′的增加而减小。

The influences of temperature on the effective mass of the weak-coupling polaron in an asymmetric parabolic quantum rod are studied based on Tokuda-Lee-Low-Pines variational method. The change law of the effective mass m＊ of the weak-coupling polarons with the aspect ratio e′ of the quantum rod, the electron-phonon coupling strength α and the temperature parameter γ are derived. Numerical results indicate that the horizontal effective mass m＊‖ and the vertical effective mass mz of the weak-coupling polaron in quantum rod will increase with the increase of the electron-phonon coupling strength α, and decrease with the increase of temperature T. The horizontal effective mass m＊‖ of the polaron will increase with the increase of the aspect ratio e′ of the quantum rod. On the contrary, the vertical effective mass mz of the polaron will decrease with the increase of the aspect ratio e′.