Force and magnetic field sensor based on measurement of tunneling conductance between ends of coaxial carbon nanotubes

TL;DR

This paper proposes a novel force and magnetic field sensor utilizing tunneling conductance measurements between coaxial carbon nanotubes, analyzing their interaction energy, and establishing a relation between conductance and force for sensing applications.

Contribution

It introduces a new sensor design based on tunneling conductance between coaxial nanotubes and models its operation for force and magnetic field detection.

Findings

Interaction energy analysis identifies optimal nanotube configurations.

A general scheme for a nanotube-based force sensor is proposed.

Operational characteristics for magnetic field sensing are estimated.

Abstract

The interaction and tunneling conductance between oppositely located ends of coaxial carbon nanotubes are studied by the example of two (11,11) nanotubes with open ends terminated by hydrogen atoms. The Green function formalism is applied to determine the tunneling current through the nanotube ends as a function of the distance between the ends, relative orientation of the nanotubes and voltage applied. The energy favorable configuration of the coaxial nanotubes is obtained by the analysis of their interaction energy at different distances between the nanotube ends and angles of their relative rotation. Using these calculations, a general scheme of the force sensor based on the interaction between ends of coaxial nanotubes is proposed and the relation between the tunneling conductance and measured force is established for the considered nanotubes. The operational characteristics of this device as a magnetic field sensor based on measurements of the magnetic force acting on the coaxial nanotubes filled with magnetic endofullerenes are estimated.