磁场和温度对束缚磁极化子有效质量的影响

Influence of the Magnetic Field andTemperature on the Effective Mass of Bound Magnetopolaron

研究强、弱耦合情形下,库仑场中束缚磁极化子的性质。采用改进的线性组合算符方法研究束缚磁极化子的振动频率和有效质量的温度依赖性,对RbCl晶体进行数值计算,结果表明:在强耦合情形下,束缚磁极化子的振动频率随温度的升高和磁场的增强而增加;有效质量随温度的增加而增加,但随磁场的增强而减少。

The cyclotron-resonance is a standard technology that determines the conductive electron and hole mass in solids. Usually the effective mass of electron is decided according to the cyclotron-resonance frequency confirmed by experiment. It should be noted that the split of cyclotron-resonance spectrum is strongly affected by the coupling of electron-phonon.Many scholars have paid much attention to the cyclotron-resonance of polaron.Zorkani et al. calcuated the ground state energy of bound magnetopolaron using variational method. Wollf et al. investigated the bound magnetic polarons in semiconductors and the bound magnetic polrons in dilute magnetic semiconductors by the optical experiments. Bouhassoune et al. studied that the magnetic field effect on the binding energy of a bound polaron in a quantum well wire.If consider the interaction between phonons of different wave vectors in the recoil process, the magnetic-field dependence of cyclotron resonance frequency, induced potential,the effectirv interaction potential, and the cyclotron-resonance mass of the surface magnetopolaron is obtained by using a linear combination operator and perturbation method by one of the authors. Li et al, calculated the temperature dependence of effective mass of strong coupling magnetopolaron in polar crystals by using different approximation methods.However,the temperature dependence of effective mass of bound magnetopolaron has not been investigated so far.The properties of a strong- or a weak-coupling bound magnetopolaron were discussed by using a linear combination operator and a unitary transformation methods by the present authors. In this paper,temperature dependence of the effective mass of the strong- or a weak-coupling bound megnetopolaron in polar crystals are studied by means of the improved linear combination operator and the Lagrange multiplier methods.The results illustrate that the vibrational frequency and the effective mass of the strong coupling bound magnetopolaron will increase with increasing temperature.The effective mass will decrease with increasing magnetic field and the vibrational frequency will increase with increasing magnetic field.