Nanomechanical displacement detection using coherent transport in ordered and disordered graphene nanoribbon resonators

TL;DR

This paper demonstrates that graphene nanoribbon resonators can be used for highly sensitive displacement detection by exploiting strain-induced changes in coherent electron transport, applicable to both ordered and disordered systems.

Contribution

It introduces a method for nanomechanical displacement detection using coherent transport in graphene nanoribbons, accounting for disorder effects.

Findings

Strain from deflections couples with electron transport in graphene nanoribbons.

Relative conductance change scales with deflection squared and inversely with length.

Applicable to both armchair and zigzag graphene nanoribbon NEMS.

Abstract

Graphene nanoribbons provide an opportunity to integrate phase-coherent transport phenomena with nanoelectromechanical systems (NEMS). Due to the strain induced by a deflection in a graphene nanoribbon resonator, coherent electron transport and mechanical deformations couple. As the electrons in graphene have a Fermi wavelength \lambda ~ a_0 = 1.4 {\AA}, this coupling can be used for sensitive displacement detection in both armchair and zigzag graphene nanoribbon NEMS. Here it is shown that for ordered as well as disordered ribbon systems of length L, a strain \epsilon ~ (w/L)^2 due to a deflection w leads to a relative change in conductance \delta G/G ~ (w^2/a_0L).