极化子比率变化对自旋注入有机半导体性质的影响(英文)  

Spin polarized injection into organic semiconductors with variational polaron proportion

作　　者：修明霞[1] 任俊峰[1] 王玉梅[1] 

机构地区：[1]山东师范大学物理与电子科学学院,济南250014

出　　处：《原子与分子物理学报》2010年第2期353-358,共6页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(10904083,10747143);山东省优秀中青年科学家科研奖励基金(2007BS01017)

摘　　要：从自旋扩散方程和欧姆定律出发研究了铁磁层到有机半导体的自旋注入,得到了系统的电流自旋极化率.有机半导体中的载流子为自旋极化子和不带自旋的双极化子,极化子比率在有机半导体内随输运距离变化.通过计算发现匹配的铁磁和有机半导体电导率有利于自旋注入;通过调节界面电阻自旋相关性,电流自旋极化率可获得很大程度提高;极化子比率衰减速率对有机半导体电流自旋极化率具有非常重要的影响.We have studied the spin polarized injection from a ferromagnetic contact into an organic semiconductor from spin diffusion theory and Ohm＇s law. Carriers in organic semiconductors include spin polarons as well as spinless bipolarons, and we assume that the variational polaron proportion decreases exponentially into the organic semiconductor in the structure of ferromagnetic/organic semiconductor. Effects of the decreasing rate of polarons on the current spin polarization are discussed. Current spin po- larization may be amplified by tuning the spin-related interracial resistances. It is also found that the conductivity matching is an important factor for efficient spin polarized injection into organic semiconductors.

关 键 词：有机自旋电子学 自旋注入 极化子 电流自旋极化率 

分 类 号：O472.5[理学—半导体物理]