title: Ferromagnetic Resonance Spin Pumping and Electrical Spin Injection in Silicon-Based Metal-Oxide-Semiconductor Heterostructures.
abstract: We present the measurement of ferromagnetic resonance (FMR-)driven spin pumping and three-terminal electrical spin injection within the same silicon-based device. Both effects manifest in a dc spin accumulation voltage V_{s} that is suppressed as an applied field is rotated to the out-of-plane direction, i.e., the oblique Hanle geometry. Comparison of V_{s} between these two spin injection mechanisms reveals an anomalously strong suppression of FMR-driven spin pumping with increasing out-of-plane field H_{app}^{z}. We propose that the presence of the large ac component to the spin current generated by the spin pumping approach, expected to exceed the dc value by 2 orders of magnitude, is the origin of this discrepancy through its influence on the spin dynamics at the oxide-silicon interface. This convolution, wherein the dynamics of both the injector and the interface play a significant role in the spin accumulation, represents a new regime for spin injection that is not well described by existing models of either FMR-driven spin pumping or electrical spin injection.
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Pu
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Odenthal
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: R
authors.initials: R
authors.lastname: Adur
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: J
authors.initials: J
authors.lastname: Beardsley
authors.affiliation: Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: A G
authors.initials: AG
authors.lastname: Swartz
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: D V
authors.initials: DV
authors.lastname: Pelekhov
authors.affiliation: Departent of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Flatté
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.|Department of Physics and Astronomy, University of California, Riverside, California 92521, USA.
authors.forename: R K
authors.initials: RK
authors.lastname: Kawakami
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: J
authors.initials: J
authors.lastname: Pelz
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: P C
authors.initials: PC
authors.lastname: Hammel
authors.affiliation: Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: E
authors.initials: E
authors.lastname: Johnston-Halperin