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arXiv · 1009.3551

Composite excitation of Josephson phase and spin waves in Josephson junctions with ferromagnetic insulator

S. Hikino·M. Mori·S. Takahashi·S. Maekawa
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Abstract

Coupling of Josephson-phase and spin-waves is theoretically studied in a superconductor/ferromagnetic insulator/superconductor (S/FI/S) junction. Electromagnetic (EM) field inside the junction and the Josephson current coupled with spin-waves in FI are calculated by combining Maxwell and Landau-Lifshitz-Gilbert equations. In the S/FI/S junction, it is found that the current-voltage (I-V) characteristic shows two resonant peaks. Voltages at the resonant peaks are obtained as a function of the normal modes of EM field, which indicates a composite excitation of the EM field and spin-waves in the S/FI/S junction. We also examine another type of junction, in which a nonmagnetic insulator (I) is located at one of interfaces between S and FI. In such a S/I/FI/S junction, three resonant peaks appear in the I-V curve, since the Josephson-phase couples to the EM field in the I layer.

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S. Hikino, M. Mori, S. Takahashi, S. Maekawa. 2011-04-14. Composite excitation of Josephson phase and spin waves in Josephson junctions with ferromagnetic insulator. https://doi.org/10.1143/jpsj.80.074707

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