Fluxon propagation on a parallel array of microbridge-type Josephson junctions

Abstract

This report describes the experimental results and theoretical considerations of the dynamic behavior and propagation of fluxons on a parallel array of the Nb microbridge-type Josephson junctions. A parallel array has 10 junctions. The spacing between adjacent junctions in an array is any one of three kinds, 2, 20, and 100 μm. For the array with 2 or 20 μm spacing, the dc current-voltage (I-V) characteristic includes a bending affecting the propagation of fluxons. In addition, the oscillation caused by the propagation of fluxons appears if impulse voltage is applied to the input terminal of the array. For the array with 100 μm spacing, on the other hand, the phenomena described above never occur. This report makes the mechanism producing these phenomena clear by numerical calculation of the equation on the equivalent circuit of the array including the measurement circuit.