Cooper-pair charge solitons: The electrodynamics of localized charge in a superconductor.

Abstract

One-dimensional arrays of small-capacitance Josephson junctions exhibit a current-voltage curve that is characterized by a zero-current state for bias voltage below a threshold voltage ${V}_{t}$. The threshold voltages can be modulated with an external magnetic field $B$, which tunes effective Josephson coupling between adjacent electrodes of the array. The dependence of ${V}_{t}$ on $B$ is well explained by a model where ${V}_{t}$ is the injection voltage for a Cooper-pair charge soliton.