铁磁/有机半导体/铁磁系统的电流自旋极化性质研究

根据有机半导体中的电流自旋极化注入和输运实验现象，理论上研究了铁磁/有机半导体/铁磁系统的电流自旋极化性质.考虑到有机半导体的具体特性，从自旋扩散理论和欧姆定律出发，得到了系统的电流自旋极化率.假设自旋极化子和不带自旋的双极化子为有机半导体中的载流子.通过计算发现，极化子为实现有机半导体中电流极化注入和输运的有效自旋载流子，即使它只占总载流子很少一部分.还进一步研究了自旋相关界面电阻和电导率匹配以及有机半导体长度等因素对系统电流自旋极化的影响. 关键词： 自旋电子学 自旋注入 有机半导体 极化子

Current spin polarization in ferromagnetic/organic semiconductor/ferromagnetic system

Based on the spin diffusion theory and the Ohm's law, we theoretically studied the spin polarized injection and transport through the ferromagnetic/organic semiconductor/ferromagnetic system and obtained the current spin polarization, which takes into account the special characteristics of organic semiconductors. Self-trapped states, such as spin polarons as well as spinless bipolarons are assumed to be the main carriers in organic semiconductors. From the calculation, it is found that polarons are the effective spin carriers in spin dependent injection and transport in organic semiconductors. The effect of the spin related interfacial resistances, conductivity match and organic semiconductor length on the current spin polarization are also discussed respectively.