Continuous room-temperature spin-injection modulation achieved by spin-filtering competition in molecular spin valves.

Abstract

Abundant spin-related phenomena that originate from interfaces between ferromagnetic electrodes and molecular semiconductors have greatly enriched research in spintronics, and they are considered promising for realizing novel spintronic functionalities in the future. However, despite great efforts, the interfacial effect cannot be precisely controlled to achieve steady and predictable functions, especially at room temperature, and this has gradually become a significant bottleneck in the development of molecular spintronics. In this study, an innovative spin-filtering-competition mechanism was first proposed to continuously modulate the interfacial effect in molecular spin valves at room temperature. To form this novel mechanism, the original spin-filtering effect from pure Co competed with the newly generated one, which was induced by the bonding effect between Co and LiF. Subsequently, by precisely controlling competition through LiF coverage on the Co surface, continuous modulation of the spin-injection process could be successfully achieved at room temperature. Spin polarization of the injected current and magnetoresistance effect could be actively controlled or their sign could be completely reversed through this novel mechanism. This study provided an innovative approach and theory for precisely controlling the spin-related interfacial effects, which may further promote the scientific and technological development of spintronics. This article is protected by copyright. All rights reserved.