MAGNETIC PHASE DIAGRAM OF SMALL SUPERCONDUCTING TWO-LOOP NETWORKS.

The critical magnetic behavior of simple superconducting micro-networks is illustrated by discussing several two-loop systems in the form of Wheatstone bridges. Using the formalism of de Gennes and Alexander it is shown how phase boundaries are obtained. These show undulating behavior for sufficiently symmetric loop systems, analogous to that of a simple loop. A physical interpretation in terms of velocities is given and new experiments are proposed.