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arXiv · 1101.1610

Josephson Tunnel Junctions in a Magnetic Field Gradient

Roberto Monaco·Jesper Mygind·Valery Koshelets
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Abstract

We measured the magnetic field dependence of the critical current of high quality Nb-based planar Josephson tunnel junctions in the presence of a controllable non-uniform field distribution. We found skewed and slowly changing magnetic diffraction patterns quite dissimilar from the Fraunhofer-like ones typical of a homogeneous field. Our findings can be well interpreted in terms of recent theoretical predictions [R. Monaco, J. Appl. Phys. vol.108, 033906 (2010)] for a uniform magnetic field gradient leading to Fresnel-like magnetic diffraction patterns. We also show that Fiske resonances can be suppressed by an asymmetric magnetic field profile.

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Roberto Monaco, Jesper Mygind, Valery Koshelets. 2011-01-08. Josephson Tunnel Junctions in a Magnetic Field Gradient. https://doi.org/10.1063/1.3555464

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