Magnetic resonance spectroscopy of perpendicularly magnetized permalloy multilayer disks

G. de Loubens (1) , V. V. Naletov (1) , Michel Viret (1) , Olivier Klein (1) , Hervé Hurdequint (2) , J. Ben Youssef (3) , F. Boust (4) , N. Vukadinovic (5)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 LPS - Laboratoire de Physique des Solides
3 LMB - Laboratoire de magnétisme de Bretagne
4 ONERA - The French Aerospace Lab [Châtillon]
5 GGT/DTIAE - Service Electromagnétisme et Infrarouge

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.

Mots clés: ferromagnetic resonance; magnetic resonance force microscopy; multilayer; nanomagnetism; spintronique

Domaines: Science des matériaux [cond-mat.mtrl-sci]

G. de Loubens, V. V. Naletov, Michel Viret, Olivier Klein, Hervé Hurdequint, et al.. Magnetic resonance spectroscopy of perpendicularly magnetized permalloy multilayer disks. 2006. ⟨hal-00113175v2⟩