title: Observation of magnon-mediated current drag in Pt/yttrium iron garnet/Pt(Ta) trilayers.
abstract: Pure spin current, a flow of spin angular momentum without flow of any accompanying net charge, is generated in two common ways. One makes use of the spin Hall effect in normal metals (NM) with strong spin-orbit coupling, such as Pt or Ta. The other utilizes the collective motion of magnetic moments or spin waves with the quasi-particle excitations called magnons. A popular material for the latter is yttrium iron garnet, a magnetic insulator (MI). Here we demonstrate in NM/MI/NM trilayers that these two types of spin currents are interconvertible across the interfaces, predicated as the magnon-mediated current drag phenomenon. The transmitted signal scales linearly with the driving current without a threshold and follows the power-law T(n) with n ranging from 1.5 to 2.5. Our results indicate that the NM/MI/NM trilayer structure can serve as a scalable pure spin current valve device which is an essential ingredient in spintronics.
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: Junxue
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Aldosary
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: Chi
authors.initials: C
authors.lastname: Tang
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: Zhisheng
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Physics, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: Shufeng
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Electrical and Computer Engineering, University of California, Riverside, California 92521, USA.
authors.forename: Roger
authors.initials: R
authors.lastname: Lake
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: Jing
authors.initials: J
authors.lastname: Shi