有机手性分子器件的光电特性

目前多种有机手性分子器件虽已研制成功,但其内在的物理机理仍有许多未解之谜,其中手性分子的圆二色性精细结构、手性诱导的自旋选择效应等是有机手性分子研究的核心。为设计基于手性的新型有机功能器件提供理论指导,考虑有机手性分子螺旋势场诱导的自旋-轨道耦合,围绕分子的光电特性及其调控展开了系列研究。根据光致跃迁理论,得到手性分子的光吸收谱和圆二色谱,发现光吸收峰发生劈裂,圆二色谱由轨道磁矩和自旋磁矩共同贡献。此外,从极化子输运的图像解释了手性诱导自旋选择效应的来源,并利用其电输运特性,设计了手性异质结器件,发现其手性电阻可达7%,整流比达48。

Photoelectric properties of organic chiral molecular devices

At present, many organic chiral molecular devices have been successfully developed, but there are still many unsolved mysteries in their functional mechanism. Among them, the sources of the circular dichroism of chiral molecules and chiral-induced spin selectivity effect are the core of organic chiral molecular researches. To provide the theoretical guidance for the design of new functional organic devices based on chirality, this paper considers the spin-orbit coupling induced by helical potential field of organic chiral molecules to carry out a series of researches on the photoelectric characteristics and regulation of organic chiral molecules. According to the photo-induced transition theory, the optical absorption spectrum and circular dichroism of chiral molecules are obtained. It is found that the optical absorption peak is split, and the circular dichroism is contributed by orbital magnetic moment and spin magnetic moment. In addition, the source of chiral induced spin selectivity effect is explained from the polaron transport picture. Based on its electrical transport characteristics, a chiral heterojunction device is designed. It is found that its chiral resistance is up to 7% and the rectification ratio is up to 48.