Superconducting d-wave junctions: The disappearance of the odd ac components

TL;DR

This paper investigates how the orientation of d-wave superconductors affects the ac Josephson components, revealing conditions where odd components vanish and the Josephson frequency doubles, with experimental comparisons and implications for current flow.

Contribution

It provides a theoretical analysis of the disappearance of odd ac components in voltage-biased d-wave junctions and compares findings with experimental data.

Findings

Odd ac components vanish at specific orientations.

Josephson frequency doubles when odd components disappear.

Sensitivity of the effect to superconductor orientation.

Abstract

We study voltage-biased superconducting planar d-wave junctions for arbitrary transmission and arbitrary orientation of the order parameters of the superconductors. For a certain orientation of the superconductors the odd ac components disappear, resulting in a doubling of the Josephson frequency. We study the sensitivity of this disappearance to orientation and compare with experiments on grain boundary junctions. We also discuss the possibility of a current flow parallel to the junction.