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arXiv · 1307.4495

Nanoscale capacitance: a classical charge-dipole approximation

Jun-Qiang Lu·Jonathan Gonzalez·Carlos Sierra·Yang Li
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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.

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Jun-Qiang Lu, Jonathan Gonzalez, Carlos Sierra, Yang Li. 2013-07-17. Nanoscale capacitance: a classical charge-dipole approximation. https://doi.org/10.1063/1.4824622

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