Explanation for the sqrt E -dependent mobilities of charge transport in molecularly doped polymers.
Explanation for the sqrt E -dependent mobilities of charge transport in molecularly doped polymers.
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分子掺杂聚合物中电荷传输的 sqrt E 相关迁移率的解释。
DOI：
10.1103/physrevb.52.939
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Dunlap
中科院分区：
文献类型：
--
作者：
Dunlap
虽然无序被广泛认为是主要的显着特点，管理运输的光注入的电荷在分子掺杂的聚合物，无序理论尚未令人信服地解释为什么线性的对数的迁移率与平方根的所施加的领域持续在这样一个广泛的范围。在这篇文章中，强无序材料的高场跳跃输运的理论相结合的连续时间随机游走与现有的可变范围跳跃技术的元素。一个自洽的积分方程推导出的网站的能量分布为特征的渗流路径的网站是确定的。该理论适用于一个能量无序系统和流动性计算的米勒-亚伯拉罕形式的跳跃率。结果表明，如果网站的能量属于高斯分布，迁移率的对数上升近线性的电场跨越近二十年的EEE。斜率与温度有关，符合Poole-Frenkel定律。
Although disorder is widely believed to be the primary distinguishing feature governing the transport of photoinjected charges in molecularly doped polymers, disorder theory has yet to convincingly explain why the linearity of the log of the mobility with the square root of the applied field persists over such a wide range. In this article a theory for high-field hopping transport in strongly disordered materials is developed which combines the elements of a continuous time random walk with existing variable-range hopping techniques. A self-consistent integral equation is derived from which the distribution of site energies for those sites which characterize the percolation pathways is determined. The theory is applied to an energetically disordered system and the mobility is calculated for the Miller-Abrahams form of the jump rate. It is shown that if the site energies belong to a Gaussian distribution, the logarithm of the mobility rises nearly linearly with√ E for electric fields spanning almost two decades. The slope is temperature dependent, and agrees with the Poole-Frenkel law.