Uncorrelated behavior of fluxoids in superconducting double networks

We study the effect of magnetic fields on the resistance R of a superconducting La_1.84Sr_0.16CuO₄ film patterned into a "double" network comprising nanosized square loops having their vertexes linked by relatively long wires. The results are compared with those obtained in a regular network of square loops of the same size. Both networks exhibit periodic dependence of R on the ratio Φ/Φ₀ between the flux penetrating a loop and the superconducting flux quantum. However, while the regular network exhibit features characteristics of collective behavior of the loops, the double network exhibits a single-loop behavior. This observation indicates uncorrelated arrangements of fluxoids in the double network, in agreement with a recent theoretical prediction.