利用幺正变换和变分法研究了柱形量子线中温度对极化子性质的影响.计算了柱形量子线中极化子的基态和第一激发态能量.数值计算结果表明,当温度参数γ〉1,即kBT〈hhwlo时,极化子基态和第一激发态能量不随温度的变化而变化;当0〈γ〈1,即kBT〉hhwlo时,基态和第一激发态能量随温度的升高而增加.而当温度一定时,基态和第一激发态能量随半径的增大而减小,说明了柱形量子线具有明显的量子尺寸效应.
With the use of the unitary transformation and the variational methods, this paper studied the influences of tempreture on properties of polaron in cylindrical wires. The ground and first internal excited energy were calculated. The numerical results show that the polaron's ground and the first excited state energies will not vary with the temperature when the temperature parameter satisfies γ〉 1 , namely kBT 〈2 halo) ; They will increase with increasing temperature when the temperature parameter satisfies 0 〈2 γ 〈2 1 , namely kBT 〉hwlo). However, when the temperature is constant, they will decrease with increasing the wire's radius, which indicates the obvious quantum size effects of the cylindrical quantum wire.