Magnetically Dependent Superconducting Transport in Oxide Heterostructures with an Antiferromagnetic Layer

Artikel i vetenskaplig tidskrift, 2008

The superconducting current in hybrid superconducting structures Nb/Au/Ca 1 − x Sr x CuO 2 /YBa 2 Cu 3 O 7 – δ with an antiferromagnetic layer is experimentally shown to have a Josephson nature, and the deviation from the sinusoidal dependence of the superconducting current on the phase difference between superconducting electrodes is about 20% of the second harmonic. These heterostructures are found to have sensitivity to an applied magnetic field that is much higher than that of conventional Josephson junctions. The experimental shape of the magnetic-field dependence of the critical current in the heterostructures differs from the usual Fraunhofer shape by oscillation with a significantly smaller period along a magnetic field. PACS numbers: 74.45.+c, 74.50.+r, 75.70.Cn