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Magnetic resonance spectroscopy of perpendicularly magnetized permalloy multilayer disks

G. De Loubens·V. V. Naletov·Michel Viret·Olivier Klein·Hervé Hurdequint·J. Ben Youssef·F. Boust·N. Vukadinovic
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Abstract

Using a Magnetic Resonance Force Microscope, we compare the ferromagnetic resonance spectra of individual micron-size disks with identical diameter, 1 $m$m, but different layer structures. For a disk composed of a single 43.3 nm thick permalloy (Py) layer, the lowest energy mode in the perpendicular configuration is the uniform precession. The higher energy modes are standing spin-waves confined along the diameter of the disk. For a Cu(30)/Py(100)/Cu(30) nm multilayer structure, it has been interpreted that the lowest energy mode becomes a precession localized at the Cu/Py interfaces. When the multilayer is changed to Py(100)/Cu(10)/Py(10) nm, this localized mode of the thick layer is coupled to the precession of the thin layer.

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G. De Loubens, V. V. Naletov, Michel Viret, Olivier Klein, Hervé Hurdequint, J. Ben Youssef, F. Boust, N. Vukadinovic. 2006-12-13. Magnetic resonance spectroscopy of perpendicularly magnetized permalloy multilayer disks. https://doi.org/10.1063/1.2711699

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