Time response of small capacitance tunnel junctions and the simulation of fast logic circuits

A simulation method of small time constant Josephson tunnel junctions is developped. It is based on a first order series expansion of the time dependent Josephson current given by the microscopic BCS theory. The method is well adapted to the switching dynamic of logic gates when the RSJC model lacks of accuracy, has a comparable efficiency both in computer time and memory space. The scaling down of resistively coupled logic gates is presented among the illustrations.