Proximity magnetoresistance in graphene induced by magnetic insulators

Article

关键词: ELECTRONIC-PROPERTIES;    EPITAXIAL GRAPHENE;    SPIN TRANSPORT;    RELAXATION;   

DOI  :  10.1103/PhysRevB.100.104402

来源: SCIE

【 摘 要 】

We demonstrate the existence of the giant proximity magnetoresistance (PMR) effect in a graphene spin valve where spin polarization is induced by a nearby magnetic insulator. PMR calculations were performed for yttrium iron garnet (YIG), cobalt ferrite (CFO), and two europium chalcogenides EuO and EuS. We find significant PMR (up to 100%) values defined as a relative change of graphene conductance with respect to parallel and antiparallel alignment of two proximity-induced magnetic regions within graphene. Namely, for high Curie temperature (T-c) CFO and YIG insulators, which are particularly important for applications, we obtain 22% and 77% at room temperature, respectively. For low T-c chalcogenides, EuO and EuS, the PMR is 100% in both cases. Furthermore, the PMR is robust with respect to system dimensions and edge-type termination, and it even maintains significant values (around 50% for YIG) in the presence of considerable spin-orbit coupling strength. Our findings show that it is possible to induce spin-polarized currents in graphene with no direct injection through magnetic materials.

【 授权许可】

Free