(Invited) Importance of Interface Engineering in Organic Spintronics
Currently, there are two major interests in organic spintronics technology. One of them is to realize a system enabling the injection/transport/detection of spin polarized charge carriers in organic semiconductors. The other one is to understand and explore the magnetic field effects (MFEs) of organic semiconductors for the development and improvement of organic-based devices such as organic light emitting diodes and magnetic sensors.
It has been known that in organic-based devices, the interfaces between active materials play a critical role in their performance and functionality because the interfaces greatly affect the injection/transport/extraction of charge carriers in organic semiconductors. Recent findings suggest that the interface engineering is also very crucial in organic spintronics technology such as enabling efficient spin-polarized charge carrier injection and tuning of organic MFEs.[5-7]
In this presentation, we will discuss our efforts towards the realization of efficient spin injection and transport in organic semiconductors as well as the modification of organic MFEs by interface engineering. We experimentally show the importance of band alignment between a metal electrode and an organic semiconductor at their interface for efficient spin injection/detection. We will also show how one can utilize a molecular self-assembled monolayer by inserting it between a metal electrode and an organic semiconductor in order to change the characteristics of spin injection into an organic semiconductor from a ferromagnetic metal as well as in order to tune the organic MFEs.
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