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arXiv · 0910.3030

Transverse instabilities of multiple vortex chains in superconductor-ferromagnet bilayers

G. Karapetrov·M. V. Milošević·M. Iavarone·J. Fedor·A. Belkin·V. Novosad·F. M. Peeters
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Abstract

Using scanning tunneling microscopy and Ginzburg-Landau simulations we explore vortex configurations in magnetically coupled NbSe$_2$-Permalloy superconductor-ferromagnet bilayer. The Permalloy film with stripe domain structure induces periodic local magnetic induction in the superconductor creating a series of pinning-antipinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-1D arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes non-linear due to a change in both the number of vortices and the confining potential. The longitudinal instabilities of the resulting vortex structures lead to vortices `levitating' in the anti-pinning channels.

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G. Karapetrov, M. V. Milošević, M. Iavarone, J. Fedor, A. Belkin, V. Novosad, F. M. Peeters. 2009-10-16. Transverse instabilities of multiple vortex chains in superconductor-ferromagnet bilayers. https://doi.org/10.1103/physrevb.80.180506

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