Discreteness effects on the fluxon interaction with the dipole impurity in the Josephson transmission line

Abstract

The influence of discreteness on the fluxon scattering on the dipole-like impurity is studied. This kind of impurity is used to model the qubit inductively coupled to the Josephson transmission line (JTL). The previously proposed fluxon assisted readout process of the qubit state is based on measuring the passage time through the dipole impurity. The aim of this work is to clarify the role of the discreteness in this qubit readout process. It is demonstrated that the fluxon delay time on the qubit impurity increases significantly if the discreteness of the JTL increases. Also it is shown that the difference between the fluxon threshold currents for the positive and negative impurities decreases with the increase of discreteness.