To deal with the Hamiltonian model in InAs QDs with a single electron, we've taken the SO interaction as a perturbation term, calculated the SO matrix elements under Fock-Darwin eigenfunction which are used for second order corrections on the energies and wave functions, and considered the influence of new energy levels on g factor and effective mass m*. The expression of phonon-assisted electron spin relaxation rate Г in InAs QDs is deduced, which shows different dependences on confined potential frequency ω0, temperature T, vertical height z0 and magnetic field B. Among them, temperature for the electron spin relaxation plays a dominant role, followed by lateral confinement potential frequency, magnetic field and the vertical height, in order of importance. ( 1 ) Growth of ω0, which corresponds to the decrease of the effective transverse size d in InAs QDs, suppresses the increase of the rate Г. (2) The temperature T affects the rateГ evidently, which will reduce the inhibition of ω0 onГ. With increase of the temperature from 1 K to 7 K, the spin inversion relaxation rate grows explosively from 103 s -1 to 108 s-1. (3) The rateГ decreases with the growth of the vertical height z0 and have the order of magnitude 100 - 103 s -1 at T = 1 K, whereas the influence of the temperature increase (at T = 6 K) on the rate will gradually exceed that of the height growth. (4) At different frequencies ω0 all curves of the rate Г versus magnetic field B have a peak that almost appears at the same field, which is attributed to the contribution of the Zeeman term (H)z exceeding that of (H)so since there is a considerable g factor in InAs material.%本文在处理InAs单电子量子点哈密顿模型时,将自旋-轨道(SO)相互作用作为微扰项,计算在Fock-Darwin本征函数下SO相互作用的矩阵元,利用其对能级和波函数的二阶修正,并且考虑新的能级对g因子和有效质量m*的影响,计算得到在声子协助下电子的自旋弛豫率Γ的表达式.给出了InAs量子点中声子协助的电子自旋弛豫率Γ对于限制势频率ω0.、温度T、纵向高度z0及磁场B等参量有不同的依赖关系,其中温度对于电子的自旋弛豫起着主导作用,横向限制势频率次之,磁场和纵向高度的作用再次之.1)在InAs量子点中,ω0的增加对应着有效横向尺寸d的变小,对Γ的值有明显的抑制作用;2)随着T的提高ω0对于电子自旋反转的抑制作用逐渐减弱,T对Γ的影响明显,从1 K增加到7 K时自旋反转弛豫迅速增加,Γ从103s-1增加到108s-1量级;3)Γ随高度z0的增加而变小,在T=1 K时厂总的量级为100-103s-1,而随着T的增加(T=6K)它将逐渐超过z0的增加对弛豫率Γ的影响;4)Γ随磁场B变化曲线在不同的ω0时均形成一个峰值,而峰值几乎出现在同一B值,这归因于InAs有相当大的g因子使得随磁场增加时塞曼项^Hz对能级产生影响将超过^HSO.
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