Detail:
Abstract: Hybrid ferromagnetic metal/organic interface, as known as “spinterfaceâ€, can exhibit highly efficient spin-filtering properties and therefore present a promising class of materials for future spintronic devices. The spin-polarization of spinterface at Fermi level can be different or even opposite in sign to that of adjacent ferromagnetic electrode. To achieve desired injection of spin-polarization, one should carefully engineer the organic/ferromagnetic interface to precisely tailor their electronic properties. Here, by using ferroelectric organic material poly(vinylidene fluoride) (PVDF), we demonstrate that the spin-polarization of the PVDF/Co spinterface can be actively controlled by tuning the ferroelectric polarization of PVDF. In particular, we have fabricated organic multiferroic tunnel junctions (MFTJs) based on La0.6Sr0.4MnO3/PVDF/Co structures. The tunneling magnetoresistance (TMR) sign can be changed by electrically switching the ferroelectric polarization of PVDF barrier. This study opens new functionality in controlling the injection of spin polarization into organic materials via the ferroelectric polarization of the barrier.
