声子色散和磁场对极化子基态的影响

Influence of Phonon Dispersion,Magnetic Field and Coupling Strength on Properties of Polaron

采用线性组合算符和幺正变换的方法,得出极化子基态能量与色散系数、耦合强度以及磁场强度之间的关系.数值计算表明:对弱耦合极化子,振动频率λ随磁场强度的增大而单调增大;基态能量E0随磁场强度增大而增大、随耦合系数α增大而单调下降、随色散系数γ增大而减小.对强耦合极化子,基态能量E0随磁场强度增大而增大、随耦合系数α增大而单调下降、与声子色散无关.

The relations of the ground state energy with the coefficient of dispersion, strength and magnetic field strength are derived by using linear- combination operator and unitary transformation method. Numerical calculations illustrated that the vibration frequency λ monotonously rises with increasing cyclotron - resonance frequency ωc ; the ground state energy E0 rises with increasing ωc and monotonously decreases with increasing a . When phonon dispersion was considered, the E0 of the weak coupling polaron decreases with increasing the coefficient of phonon dispersion γ, but γ has little effect on the of strong coupling polaron.