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arXiv · 1601.03133

Spin Vortex Resonance in Non-planar Ferromagnetic Dots

Junjia Ding·Pavel Lapa·Shikha Jain·Trupti Khaire·Sergi Lendinez·Wei Zhang·Matthias B. Jungfleisch·Christian M. Posada·Volodymyr G. Yefremenko·John E. Pearson·Axel Hoffmann·Valentine Novosad
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Abstract

In planar structures, the vortex resonance frequency changes little as a function of an in-plane magnetic field as long as the vortex state persists. Altering the topography of the element leads to a vastly different dynamic response that arises due to the local vortex core confinement effect. In this work, we studied the magnetic excitations in non-planar ferromagnetic dots using a broadband microwave spectroscopy technique. Two distinct resonance frequency ranges were observed depending on the position of the vortex core controllable by applying a relatively small magnetic field. The micromagnetic simulations are in qualitative agreement with the. experimental results.

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Junjia Ding, Pavel Lapa, Shikha Jain, Trupti Khaire, Sergi Lendinez, Wei Zhang, Matthias B. Jungfleisch, Christian M. Posada, Volodymyr G. Yefremenko, John E. Pearson, Axel Hoffmann, Valentine Novosad. 2016-01-13. Spin Vortex Resonance in Non-planar Ferromagnetic Dots. https://arxiv.org/abs/1601.03133

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