Tunable Supercurrent at the Charge Neutrality Point via Strained Graphene Junctions

TL;DR

This paper presents a theoretical study showing that mechanical strain can effectively tune the supercurrent at the charge neutrality point in graphene junctions, with potential for controlling superconducting properties.

Contribution

The work introduces a method to control supercurrent in graphene via strain, considering both monolayer and bilayer systems, and analyzes the impact on Fano factor behavior.

Findings

Supercurrent at charge neutrality can be enhanced or suppressed by strain.

Strain direction significantly affects supercurrent and Fano factor.

Theoretical framework applicable to both monolayer and bilayer graphene.

Abstract

We theoretically calculate the charge-supercurrent through a ballistic graphene junction where superconductivity is induced via the proximity-effect. Both monolayer and bilayer graphene are considered, including the possibility of strain in the systems. We demonstrate that the supercurrent at the charge neutrality point can be tuned efficiently by means of mechanical strain. Remarkably, the supercurrent is enhanced or suppressed relative to the non-strained case depending on the direction of this strain. We also calculate the Fano factor in the normal-state of the system and show how its behavior varies depending on the direction of strain.