We demonstrate that a multiply connected superconducting structure in combination with a perpendicularly magnetized magnetic dot can be used as a current source for superconducting elements and as an external phase shifter. The concept has been tested by measuring the superconducting Tc(B) phase boundary and critical current of an Al superconducting loop placed on the top of a micron-sized Co∕Pd magnetic dot. A pronounced asymmetry in the voltage–current characteristic of the loop with respect to the polarity of the external magnetic field, as well as a shift of the Tc(B) phase boundary along the field axis indicate the presence of a persistent current in the loop.We demonstrate that a multiply connected superconducting structure in combination with a perpendicularly magnetized magnetic dot can be used as a current source for superconducting elements and as an external phase shifter. The concept has been tested by measuring the superconducting Tc(B) phase boundary and critical current of an Al superconducting loop placed on the top of a micron-sized Co∕Pd magnetic dot. A pronounced asymmetry in the voltage–current characteristic of the loop with respect to the polarity of the external magnetic field, as well as a shift of the Tc(B) phase boundary along the field axis indicate the presence of a persistent current in the loop.
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