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arXiv · 0809.1743

Suppression of dissipation in Nb thin films with triangular antidot arrays by random removal of pinning sites

M. Kemmler·D. Bothner·K. Ilin·M. Siegel·R. Kleiner·D. Koelle
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Abstract

The depinning current Ic versus applied magnetic field B close to the transition temperature Tc of Nb thin films with randomly diluted triangular arrays of antidots is investigated. % Our experiments confirm essential features in Ic(B) as predicted by Reichhardt and Olson Reichhardt [Phys.Rev. B 76, 094512 (2007)]. % We show that, by introducing disorder into periodic pinning arrays, Ic can be enhanced. % In particular, for arrays with fixed density n_p of antidots, an increase in dilution Pd induces an increase in Ic and decrease of the flux-flow voltage for B>Bp=n_p Phi_0.

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M. Kemmler, D. Bothner, K. Ilin, M. Siegel, R. Kleiner, D. Koelle. 2008-09-10. Suppression of dissipation in Nb thin films with triangular antidot arrays by random removal of pinning sites. https://doi.org/10.1103/physrevb.79.184509

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