During the past years, charge transport performance of solution-processed donor-acceptor (D-A) conjugated polymers has been explosively studied for successful instance of record-breaking carrier mobility. By contrast, corresponding spin dynamics was far-less probed except handful pioneering reports. Herein, we successfully observed room-temperature stable magnetoresistance (MR) response in organic spin valves using ambipolar naphthalenediimide-based D-A type conjugated polymers. Additionally, we found spin transport performance of these polymer-inserted junction was sensitive to chemical structures of polymer repeating units. Both alkyl-chain extension in the acceptor unit and cyano-group substitution in the donor unit can induce evident MR drop. Furthermore, we discovered spin dynamics inside these ambipolar materials exhibited disparate electrical dependence from classical unipolar small-molecule medium. Neither increased bias current size nor reversed polarity can downsize junction MR response in the spin valves based on these conjugated polymers hence verified underlying great potential of ambipoalr media in spintronics devices. We would like to emphasize that no spinterface effect happened even when these solution-processed polymers contacted directly with ferromagnetic electrodes according to comprehensive magnetization study. This spin-related exploration opened a new avenue to understand spintronics from material level, and also unveiled inspiring potential of solution-processed D-A type conjugated polymers on future spin-memory devices.

在过去的几年中，溶液处理的施主-受主（DA）共轭聚合物的电荷传输性能得到了爆炸性的研究，成功地打破了载流子迁移率的记录。相比之下，除了少数先驱报道外，还没有探讨相应的自旋动力学。在这里，我们成功地观察到了使用双极性萘二甲酰亚胺基DA型共轭聚合物的有机自旋阀中的室温稳定磁阻（MR）反应。此外，我们发现这些聚合物插入的结的自旋输运性能对聚合物重复单元的化学结构敏感。受体单元中的烷基链延伸和供体单元中的氰基取代都可引起明显的MR下降。此外，我们发现这些双极性材料内部的自旋动力学表现出与经典单极性小分子介质完全不同的电依赖性。基于这些共轭聚合物，增加的偏置电流大小和相反的极性都不能减小自旋阀中的结MR响应，因此证明了自旋电子学器件中双歧介质的巨大潜力。我们要强调的是，根据全面的磁化研究，即使这些固溶处理的聚合物直接与铁磁电极接触，也不会发生界面效应。这项与自旋有关的探索开辟了从材料层面理解自旋电子学的新途径，并且还揭示了溶液处理的DA型共轭聚合物在未来自旋记忆器件上的启发性潜力。