arXiv 0812.46082008-12-25cond-mat.supr-concond-mat.mes-hall

Strong influence of a magnetic layer on the critical current of Nb bridge in finite magnetic fields due to surface barrier effect

D. Y. Vodolazov, B. A. Gribkov, A. Yu. Klimov, V. V. Rogov, S. N. Vdovichev

备注：: 4 pages, 3 figures
DOI：: 10.1063/1.3030983

英文摘要：

We measured the critical current of the bilayer Nb/Co in the applied magnetic field. When the magnetic field was tilted to the axis which was perpendicular to the plane of the bilayer we observed a large difference in critical currents flowing in opposite directions. We found that the largest critical current of the bilayer exceeded the critical current of the superconductor without Co layer in a wide range of the tilted magnetic fields. The theory which takes into account the surface barrier effect for vortex entry and magnetic field of the magnetic layer gave a quantitative explanation of our experimental results.

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