5 O ct 1 99 9 A theory of π / 2 superconducting Josephson junctions
نویسنده
چکیده
We consider theoretically a Josephson junction with a superconducting critical current density which has a random sign along the junction's surface. We show that the ground state of the junction corresponds to the phase difference equal to π 2. Such a situation can take place in superconductor-ferromagnet-superconductor junctions.
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