Inductance calculation system for superconducting circuits

A method for calculating the inductance of complicated three-dimensional superconducting circuits is described. The current distribution is obtained by assuming that the edge currents satisfy both Maxwell's and London's equations. Inductance is calculated from the magnetic energy resulting from the current. Extrapolations are used to reduce the computational requirements and to increase the accuracy of the results. Using the method, a CAD (computer-aided design) system was developed for superconducting circuits. The inductance of 3-D superconducting circuits, which was unattainable except by experiments, can be easily calculated by this system. The coupling inductance of a DC SQUID (superconducting quantum interference device) is calculated using the CAD system. Agreement between experiment and the computation is good.<
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