束缚极化子有效质量的温度特性

采用改进的线性组合算符和幺正变换方法研究强、弱耦合束缚极化子的有效质量的温度特性,对RbCl晶体进行数值计算。结果表明,强耦合束缚极化子的振动频率和有效质量随温度的升高而增加,随库仑势的增加而增大。

Temperature Properties of the Effective Mass of Bound Polaron

The problems of an electron bound in a hydrogenic impurity and interacting with the longitudinal optical phonon field of an ionic crystal or a polar semiconductor have been of considerable interest. Since To-kuda investigated the problem of bound polaron by using variational scheme of the Lee-Low-Pines theory, many investigators studied the properties of the bound polaron by means of various theoretical methods and experimental methods. Lepine et al. studied the properities of bound polaron in a narrow-band polar crystal within the scheme of effective-mass approximation. Chen et al. studied properties of bound polaron in parabolic quantum wire by using the Feynmann-Haken path-integral approach.Liang et al. investigated binding energy of bound polaron in ternarg mixed crystals, taking into account the interaction of an electron with two branch longitudinal optical phonon.Es-sbai studied LO phonons effect on the binding energy of impurity bound polaron in 3D GaAs quantum dot by using variational method. Molnikov discussed the effect of the electron-phonon interaction on an electron bound to an impurity in a spherical quantum dot by using adiabatic variational method. Devreese studied properities of bound polaron in oxide compounds by using quantum-chemical method.The properties of a strong or a weak coupling bound magnetopolaron was discussed by using a linear combination operator and a unitary transformation methods by the present authors. In the past, most work was devoted at zero temperature.In fact, the case of a finite temperature is more significant.However, the temperature dependence of the properties of bound polaron has not been studied so far.In this paper, the temperature dependence of effective mass of bound optical polaron which is in a strong or a weak-coupling with optical phonon was calculated by using improved linear combination operator and unitary transformation method. Numerical calculations, for the RbCl crystal, as an example, are pertormed and the results illustrate that the vibrational frequency and the effective mass of the strong-coupling bound polaron increase with increasing the temperature and the Coulomb potential.