Nanoscale capacitance: a classical charge-dipole approximation

TL;DR

This paper introduces a classical charge-dipole model to accurately calculate nanoscale capacitance, accounting for electrode effects often neglected in macroscopic models, demonstrated on carbon nanotube nano-gaps.

Contribution

It presents a novel classical atomic charge-dipole approximation model for nanoscale capacitance, including effective capacitance definitions and electrode influence.

Findings

Capacitance increases with electrode length in nano-gaps

Electrode effects significantly influence nanoscale circuit properties

Model successfully applied to carbon nanotube and buckyball configurations

Abstract

Modeling nanoscale capacitance presents particular challenge because of dynamic contribution from electrodes, which can usually be neglected in modeling macroscopic capacitance and nanoscale conductance. We present a model to calculate capacitances of nano-gap configurations and define effective capacitances of nanoscale structures. The model is implemented by using a classical atomic charge-dipole approximation and applied to calculate capacitance of a carbon nanotube nano-gap and effective capacitance of a buckyball inside the nano-gap. Our results show that capacitance of the carbon nanotube nano-gap increases with length of electrodes which demonstrates the important roles played by the electrodes in dynamic properties of nanoscale circuits.