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arXiv · 1107.3743

Enhancement of vortex pinning in superconductor/ferromagnet bilayers via angled demagnetization

Marta Z. Cieplak·L. Y. Zhu·Z. Adamus·M. Konczykowski·C. L. Chien
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Abstract

We use local and global magnetometry measurements to study the influence of magnetic domain width w on the domain-induced vortex pinning in superconducting/ferromagnetic bilayers, built of a Nb film and a ferromagnetic Co/Pt multilayer with perpendicular magnetic anisotropy, with an insulating layer to eliminate proximity effect. The quasi-periodic domain patterns with different and systematically adjustable width w, as acquired by a special demagnetization procedure, exert tunable vortex pinning on a superconducting layer. The largest enhancement of vortex pinning, by a factor of more than 10, occurs when w ~ 310 nm is close to the magnetic penetration depth.

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Marta Z. Cieplak, L. Y. Zhu, Z. Adamus, M. Konczykowski, C. L. Chien. 2011-07-19. Enhancement of vortex pinning in superconductor/ferromagnet bilayers via angled demagnetization. https://doi.org/10.1103/physrevb.84.020514

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