Nonreciprocal transmission of microwaves through a long Josephson junction

TL;DR

This paper investigates how long Josephson junctions can be used to achieve nonreciprocal microwave transmission, with maximum attenuation depending on flux flow direction and system parameters.

Contribution

It provides an analytical and numerical analysis of nonreciprocal microwave transmission in long Josephson junctions within the flux-flow regime, highlighting conditions for maximum attenuation.

Findings

Maximum attenuation occurs when flux flow opposes microwave propagation.

Attenuation is enhanced by increasing system length and impedance matching.

Nonreciprocal transmission depends on flux flow direction and junction parameters.

Abstract

Nonreciprocal microwave transmission through a long Josephson junction in the flux-flow regime is studied analytically and numerically within the framework of the perturbed sine-Gordon model. We demonstrate that the maximum attenuation of the transmitted power occurs when the direction of the flux flow is opposite to the direction of the microwave propagation. This attenuation is nonreciprocal with respect to the flux-flow direction and can be enhanced by increasing the system length and proper impedance matching of the junction ends to external transmission line.