People: G. de Loubens (Permanent staff)
Alumni: B. Pigeau (PhD)
Collaborations:
Fundings: ANR VOICE (2009-2012) et TOPSKY (2017-2020)
Fig.1. Spin-wave modes in the cone state. (a) MRFM spectra obtained on an individual disk of NiMnSb of diameter 1 µm. (b) Dispersion relation of the different spin-wave modes observed experimentally. (c), (d) Micromagnetic simulation of the spin-wave spectra as a function of the perpendicular field Hz. Modes are labeled using their azimuthal and radial indices. The two panels differentiate spin-waves depending on their sense of gyration. Their spatial profiles in the vortex (µ0Hz=0 T) and saturated states (µ0Hz=2 T) are shown on the left and right sides, respectively.
Fig.2. MRFM spectroscopy of the vortex core confinement potential. (a) Side and (b) top views of the experimental setup:the stray field of the MRFM tip is used to displace the static position of the vortex core. (c) Plot of the relative variation of eigenfrequency of the gyrotropic mode as a function of the latter. (d) Relative variation of the eigenfrequency as a function of the tip displacement. The lines show the analytical behaviors for a vanishing and a finite anharmonic coefficient.
[1] V. Castel, J. Ben Youssef, F. Boust, R. Weil, B. Pigeau, G. de Loubens, V. V. Naletov, O. Klein, N. Vukadinovic, Perpendicular ferromagnetic resonance in soft cylindrical elements: Vortex and saturated states, Phys. Rev. B 85, 184419 (2012).
[2] B. Taurel, T. Valet, V. V. Naletov, N. Vukadinovic, G. de Loubens, O. Klein, Complete mapping of the spin-wave spectrum in a vortex-state nanodisk, Phys. Rev. B 93, 184427 (2016).
[3] B. Pigeau, G. de Loubens, O. Klein, A. Riegler, F. Lochner, G. Schmidt, L.W. Molenkamp, Optimal control of vortex-core polarity by resonant microwave pulses, Nature Phys., 7, 26–31 (2011).
[4] G. de Loubens, A. Riegler, B. Pigeau, F. Lochner, F. Boust, K. Y. Guslienko, H. Hurdequint, L. W. Molenkamp, G. Schmidt, A. N. Slavin, V. S. Tiberkevich, N. Vukadinovic, O. Klein, Bistability of Vortex Core Dynamics in a Single Perpendicularly Magnetized Nanodisk, Phys. Rev. Lett. 102, 177602 (2009).
[5] B. Pigeau, G. de Loubens, O. Klein, A. Riegler, F. Lochner, G. Schmidt, L.W. Molenkamp, V.S. Tiberkevich, A.N. Slavin, A frequency-controlled magnetic vortex memory, Appl. Phys. Lett. 96, 132506 (2010).
[6] O. V. Sukhostavets, B. Pigeau, S. Sangiao, G. de Loubens, V. V. Naletov, O. Klein, K. Mitsuzuka, S. Andrieu, F. Montaigne, K. Y. Guslienko, Probing the Anharmonicity of the Potential Well for a Magnetic Vortex Core in a Nanodot, Phys. Rev. Lett. 111, 247601 (2013).