Development of high spin-polarization spintronic devices based on organic molecular semiconductors

自旋电子学将电子的自旋和电荷特性应用于信息存储和处理，作为一种有前途的替代基于金属氧化物半导体(CMOS)的互补电子技术的技术，正引起学术界和工业界的极大关注。在过去的几十年里，这种技术几乎在各个方面都对我们的生活产生了巨大的影响。特别是，有机电子学的最新进展不仅为高能效、机械灵活和大面积电子学开辟了道路，而且使分子半导体在自旋电子学应用中具有极大的吸引力，因为它们可以长期和远距离地保存基于自旋的信息。然而，尽管全世界在有机自旋电子学领域进行了大量的研究工作，但在晶体管结构中高效的自旋注入/输运仍然是开发包括有机自旋阀和自旋场效应晶体管(Spin-FET)在内的实用自旋电子器件的长期挑战。这与磁性材料与有机半导体之间的界面问题密切相关，如大的电导失配、强的自旋-表面偶极相互作用和结构缺陷，这些缺陷阻碍了自旋载流子有效地注入有机半导体层。为了克服这些问题，实现实用的自旋电子器件，设计新的结构，使自旋转移过程的效率最大化，并使用适当的表征工具来研究它们的磁/电性质是至关重要的。这项拟议的研究旨在阐明自旋电子器件中自旋注入和输运的详细机制，并开发可在磁场和电场中操作的磁强型有机自旋阀和自旋场效应晶体管。

Spintronics, where both spin and charge properties of electrons are applied to information storage and processing, is garnering tremendous attention from academia and industry as a promising alternative to the complementary metal-oxide-semiconductor (CMOS)-based electronics technology which has impacted immensely on our lives in nearly all aspects for past decades. Especially, recent progress in organic electronics has not only opened the way to the energy-efficient, mechanically flexible, and large-area electronics, but also made molecular semiconductors very attractive for spintronics applications since they can preserve the spin-based information over long time and distance. However, despite intensive research efforts in the field of organic spintronics worldwide, highly efficient spin-injection/transport in transistor-like structures still remains a long-standing challenge in the development of practical spintronic devices including organic spin-valves and spin field-effect transistors (spin-FETs). This is strongly correlated with the interface problems between magnetic materials and organic semiconductors, such as large conduction mismatch, strong spin-surface dipole interaction, and structural defects, which prevent efficient injection of spin carriers into organic semiconductor layer. To overcome these problems and realize practical spintronic devices, it is crucial to devise new architectures, which maximize the efficiency of spin-transfer process, and to investigate their magnetic/electronic properties using the adequate characterization tools. The proposed research aims to shed light on the detailed mechanism of spin-injection and transport in spintronic devices and to develop magnetically robust organic spin-valves and spin-FETs operatable in both magnetic and electric fields.