Microscopic investigation into the electric field effect on proximity-induced magnetism in Pt

Authors

K. T. Yamada, M. Suzuki, A.-M. Pradipto, T. Koyama, S. Kim, K.-J. Kim, S. Ono, T. Taniguchi, H. Mizuno, F. Ando, K. Oda, H. Kakizakai, T. Moriyama, K. Nakamura, D. Chiba, and T. Ono

Abstract

Electric field effects on magnetism in metals have widely attracted attention but the microscopic mechanism is still controversial. We experimentally show the relevancy between the electric field effect on magnetism and on the electronic structure in a ferromagnetic metal using element-specific measurements: X-ray magnetic circular dichroism (XMCD) and absorption spectroscopy (XAS). Electric fields are applied to the surface of an ultrathin metallic Pt, at which a magnetic moment is induced by the ferromagnetic proximity effect resulting from a Co underlayer. XMCD and XAS measurements performed under the application of electric fields reveal that both the spin and the orbital magnetic moments of Pt atoms are electrically modulated, which can be explained not only by the electric-field-induced shift of the Fermi level but also by the change in the orbital hybridizations.

Physical Review Letters：https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.157203