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arXiv · 0904.1780

Coupled Superconducting Phase and Ferromagnetic Order Parameter Dynamics

I. Petkovic·M. Aprili·S. E. Barnes·F. Beuneu·S. Maekawa
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Abstract

Via a direct coupling between the magnetic order parameter and the singlet Josephson supercurrent, we detect spin-wave resonances, and their dispersion, in ferromagnetic Josephson junctions in which the usual insulating or metallic barrier is replaced with a weak ferromagnet. The coupling arises within the Fraunhofer interferential description of the Josephson effect, because the magnetic layer acts as a time dependent phase plate. A spin-wave resonance at a frequency ws implies a dissipation that is reflected as a depression in the current-voltage curve of the Josephson junction when hbar ws = 2eV. We have thereby performed a resonance experiment on only 10^7 Ni atoms.

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I. Petkovic, M. Aprili, S. E. Barnes, F. Beuneu, S. Maekawa. 2009-04-11. Coupled Superconducting Phase and Ferromagnetic Order Parameter Dynamics. https://doi.org/10.1103/physrevb.80.220502

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