极性晶体中磁极化子声子色散效应

Effect of phonon dispersion on magnetopolaron in a polar crystal

利用线性组合算符和幺正变换相结合的方法,研究了声子色散对极性晶体中磁极化子性质的影响。计及纵光学(LO)声子色散,在抛物近似下导出了极性晶体中磁极化子基态能量、自陷能和基态Landau能随声子色散系数、回旋共振频率和电子-纵光学声子耦合强度的变化关系。数值计算结果表明基态能量随声子色散系数、电子-纵光学声子耦合强度的增大而减小。自陷能随声子色散系数和电子-纵光学声子耦合强度的增大而增大。基态Landau能随电子-纵光学声子耦合强度的增大先增大到最大值后又减小,随声子色散系数的增大而增大。

The influence of phonon dispersion on properties of the magnetopolaron in a polar crystal was studied by using the linear combination operator and unitary transformation method. Taking account of the longitudinal optical （LO） phonon dispersion in a parabolic approximation, the ground state energy, self-trapping energy and ground state Landau energy of the magnetopolaron in a polar crystal as a function of coefficient of the phonon dispersion, cYclotron resonance frequency and electron-LO-phonon coupling constant were obtained. Numerical calculation results show that the ground state energy decreases with increasing the coefficient of the phonon dispersion and electron-LO-phonon coupling constant. The self- trapping energy increases with increasing the coefficient of phonon dispersion and the electron-LO-phonon coupling constant, The ground state Landau energy increases to a maximum and then fall with increasing the electron-LO-phonon coupling constant, and increases with increasing the coefficient of phonon dispersion.