Symmetry of trapped-field profiles in square columnar Josephson-junction arrays

The remanence of NxN square-columnar Josephson-junction arrays with normalized maximum junction current imax is calculated from the dc and ac Josephson equations, the Ampere theorem, and the gauge invariance. A transition line on the imax-N plane is obtained, on the high-imax side of which the remanence is nonzero. It is found that in the nonzero remanence state the symmetry degree of field profile can be lower than expected by intuition. The meaning and importance of this finding are discussed