Continuous modulation of charge-spin conversion by electric field in Pt/Co₂FeSi/Pb(Mg_1/3Nb_2/3)O₃- Pb_0.7Ti_0.3O₃ heterostructures

The half-metallic Heusler alloy Co2FeSi is an ideal material in spintronic devices due to its higher spin polarization, higher Curie temperature and lower damping parameters. In this work, the dynamic magnetism of Co2FeSi is modulated by electric field and it is demonstrated that the charge-spin conversion efficiency xi is continuous and controllable by the electric field. We further find an extremely high xi in ferromagnetic/ferroelectric (FM/FE) heterostructures, which could be ascribed to interfacial effect in FM/FE interface. Moreover, we investigate that the charge-spin conversion efficiency varies with the electric field in a butterfly-like behavior, which accords with the S-E curve of Pb(Mg1/3Nb2/3)O-3-Pb0.7Ti0.3O3(PMN-PT) and could be attributed to strain effect. The modulation of charge-spin conversion efficiency in FM/FE heterostructures via electric field presents a profound potential for next-generation spintronic devices and applications of current-induced magnetization switching.