Mutual-inductance route to the paramagnetic Meissner effect in two-dimensional Josephson-junction arrays

We simulate two-dimensional Josephson-junction arrays, including full mutual-inductance effects, as they are cooled below the transition temperature in a magnetic field. We show numerical simulations of the array magnetization as a function of position, as detected by a scanning superconducting quantum interference device which is placed at a fixed height above the array. The calculated magnetization images show striking agreement with the experimental images obtained by Nielsen et al. [Phys. Rev. B 62, 14 380 (2000)]. The average array magnetization is found to be paramagnetic for many values of the applied field, confirming that paramagnetism can arise from magnetic screening in multiply connected superconductors without the presence of d-wave superconductivity.