We performed a propagating spin-wave spectroscopy for backward spin-waves in ferromagnetic metallic microstructures in the presence of electric-current. Even with the smaller current injection of 5 × 1010 A m-2 into ferromagnetic microwires, the backward spinwaves exhibit a gigantic 200 MHz frequency shift and a 15% amplitude change, showing 60 times larger modulation compared to previous reports. Systematic experiments by measuring dependences on a film thickness of mirowire, on the wave-vector of spin-wave, and on the magnitude of bias field, we revealed that for the backward spin-waves a distribution of internal magnetic field generated by electric-current efficiently modulates the frequency and amplitude of spin-waves. The gigantic frequency and amplitude changes were reproduced by a micromagnetics simulation, predicting that the current-injection of 5 × 1011 A m-2 allows 3 GHz frequency shift. The effective coupling between electric-current and backward spinwaves has a potential to build up a logic control method which encodes signals into the phase and amplitude of spin-waves. The metallic magnonics cooperating with electronics could suggest highly integrated magnonic circuits both in Boolean and non-Boolean principles.
Bibliographical noteFunding Information:
This work was supported by the Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology (JST-PRESTO). KS also acknowledges Grants-in-Aid for Scientific Research (25706004, 16H02098, 16K13670) from the Ministry of Education, Culture Sports Science and Technology Japan. NS acknowledges Grant-in-Aid for JSPS Research Fellow(14J05944) from the Japan Society for the Promotion of Science. KJL acknowledges the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (2011-0027905, 2015M3D1A1070465).
© 2017 IOP Publishing Ltd.
- spin waves
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Acoustics and Ultrasonics
- Surfaces, Coatings and Films