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Spin-Torque Excitation of Perpendicular Standing Spin Waves in Coupled YIG/Co Heterostructures.

ABSTRACT: We investigate yttrium iron garnet (YIG)/cobalt (Co) heterostructures using broadband ferromagnetic resonance (FMR). We observe an efficient excitation of perpendicular standing spin waves (PSSWs) in the YIG layer when the resonance frequencies of the YIG PSSWs and the Co FMR line coincide. Avoided crossings of YIG PSSWs and the Co FMR line are found and modeled using mutual spin pumping and exchange torques. The excitation of PSSWs is suppressed by a thin aluminum oxide interlayer but persists with a copper interlayer, in agreement with the proposed model.

SUBMITTER: Klingler S

PROVIDER: S-EPMC6003818 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Spin-Torque Excitation of Perpendicular Standing Spin Waves in Coupled YIG/Co Heterostructures.

Klingler Stefan S Amin Vivek V Geprägs Stephan S Ganzhorn Kathrin K Maier-Flaig Hannes H Althammer Matthias M Huebl Hans H Gross Rudolf R McMichael Robert D RD Stiles Mark D MD Goennenwein Sebastian T B STB Weiler Mathias M

Physical review letters 20180301 12

We investigate yttrium iron garnet (YIG)/cobalt (Co) heterostructures using broadband ferromagnetic resonance (FMR). We observe an efficient excitation of perpendicular standing spin waves (PSSWs) in the YIG layer when the resonance frequencies of the YIG PSSWs and the Co FMR line coincide. Avoided crossings of YIG PSSWs and the Co FMR line are found and modeled using mutual spin pumping and exchange torques. The excitation of PSSWs is suppressed by a thin aluminum oxide interlayer but persists ...[more]

PMID: 29694068

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