Effect of fullerene on the anisotropy, domain size and relaxation of a perpendicularly magnetized Pt/Co/C60/Pt system

Abstract

Buckminsterfullerene (C₆₀) can exhibit ferromagnetism at the interface (called a spinterface) when it is placed next to a ferromagnet (FM). The formation of a spinterface occurs due to orbital hybridization and spin polarized charge transfer at the interface. The spinterface can influence the domain size and magnetization dynamics of the organic/ferromagnetic heterostructure. Here, we have performed magnetic domain imaging and studied the relaxation dynamics in Pt/Co/C₆₀/Pt systems which exhibit perpendicular anisotropy. The obtained results have been compared with a reference Pt/Co/Pt system. It is observed that the presence of C₆₀ in the Pt/Co/Pt system leads to an increase in perpendicular magnetic anisotropy and a decrease in the size of bubble domains. Furthermore, the switching time of the Pt/Co/C₆₀/Pt system is faster than its reference Pt/Co/Pt system. Spin polarized density functional theory (DFT) calculations have been performed to understand the underlying mechanism. The DFT results show the formation of a spin polarized spinterface which leads to an enhancement in anisotropy.