Theory of the Strain Engineering of Graphene Nanoconstrictions

TL;DR

This paper explores how strain affects the electronic properties of graphene nanoconstrictions, highlighting the interplay between pseudo-gauge fields and quantum interference, which leads to unique conductance behaviors at room temperature.

Contribution

It presents a theoretical analysis of the distinct strain dependencies of pseudo-gauge fields and quantum interference in graphene nanoconstrictions, revealing novel conductance phenomena.

Findings

Pseudo-gauge field effects are symmetric with strain.

Quantum interference effects are antisymmetric with strain.

Unique strain-dependent conductance behavior observed at room temperature.

Abstract

Strain engineering is one of the key technologies for using graphene as an electronic device: the strain-induced pseudo-gauge field reflects Dirac electrons, thus opening the so-called conduction gap. Since strain accumulates in constrictions, graphene nanoconstrictions can be a good platform for this technology. On the other hand, in the graphene nanoconstrictions, Fabry-Perot type quantum interference dominates the electrical conduction at low bias voltages. We argue that these two effects have different strain dependence; the pseudo-gauge field contribution is symmetric with respect to positive (tensile) and negative (compressive) strain, whereas the quantum interference is antisymmetric. As a result, a peculiar strain dependence of the conductance appears even at room temperatures.