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We report on the observation of the Wohlleben effect (WE) in powders of Bi-based high-temperature superconductors consisting of isolated grains with sizes of order 1 mm. In these small grains the Josephson contacts with negative critical current (π-junctions) generally involved to explain the WE must be able to carry a current density of order j ≈ 10 5 -10 6 A/cm 2 , even close to Tc. Such high spontaneous currents can be explained, if such contacts are not ordinary tunneling Josephson junctions but superconductor-normal-metal-superconductor junctions and if the superconducting order parameter has d-wave symmetry.

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