有机半导体的自旋注入和自旋输运

Spin Injection and Spin Transport in an Organic Semiconductor System

利用自旋漂移-扩散方程自洽地得到了铁磁/有机半导体自旋注入结构中极化子电导的自旋相关性对自旋注入效率的影响。计算结果表明,自旋注入效率明显依赖于极化子电导的自旋相关性。在自旋注入效率增加30%的情况下,极化子电导的自旋相关性T=5K时将增大4个数量级左右,表明,在电场作用下的有机半导体自旋注入体系中,考虑极化子电导的自旋相关性对自旋注入的影响有着非常重要的意义。另外自旋注入效率还是位置的函数,但当电场大于100mV/μm后,极化子的自旋相关性几乎不再随极化子所在位置发生变化,自旋注入效率此时也几乎与位置无关。

The effect of the spin-dependent electrical conductivity on spin injection efficiency is self-consistently derived applying the spin drift-diffusion equation on the ferromagnetic （FM）/organic （OSE） structure. The calculations show that the spin injection efficiency is evidently dependent on the spin-dependent electrical conductivity. When spin injection efficiency increases about 30% at T：SK, the spin-dependent electrical conductivity exhibits nearly 4 orders of change in magnitude. It shows that it is significant to consider effect of the spin-dependent electrical conductivity on spin injection efficiency in the spin-injected OSE system. It is also found that the spin injection efficiency is position sensitive, but its position sensitivity goes down while eleetric-fields larger than about 100mV/μm, for the spindependent electrical-conductivity isn＇t dependent on the position of the polarons any more.