Photocontrolled All-Organic Magnetoelectric Switch Based on Two Types of Charge Transfer Complexes at Room Temperature

Abstract

Integrating all optical, electrical, and magnetic properties into a single device is still difficult in the construction of multifunctional spintronic devices. Herein, by combining two kinds of charge transfer (CT) complexes in a single organic device, a polarity-adjustable room-temperature magnetoconductance (MC) has been achieved at a fixed bias voltage. Specifically, the interfacial ground-state charge transfer (GSCT) complex and the excited-state charge transfer (ESCT) complex exhibit different MC profiles and hence together generate an optical-incentive MC without any ferromagnetic electrodes. The simulation of the MC profiles suggests that the GSCT-induced hyperfine interaction (HFI) dominates in the negative MC in the dark, while the ESCT-induced Δg mechanism dominates in the positive MC with illumination. Furthermore, an ultrahigh-amplitude MC (over 10 000%) is obtained near the turn-on voltage at room temperature. More importantly, the MC responses can be controlled and manipulated by magnetic field, applied electric field, and variable intensity and wavelength of light excitation. Finally, the universality of the design principle in devices is demonstrated by the change of the series of materials, in which the electron and hole transport layers are replaced by other corresponding materials of the same type, respectively. This work offers some clues for realizing pure organic multifunctional devices coupling light-electricity-magnetism in the future.