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Fano Resonance and Orbital Filtering in Multiply Connected Carbon Nanotubes

Gunn Kim·Sang Bong Lee·Tae-Suk Kim·Jisoon Ihm
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Abstract

We investigate the electron transport in multiply connected metallic carbon nanotubes within the Landauer-Büttiker formalism. Quasibound states coupled to the incident $π^{*}$ states give rise to energy levels of different widths depending on the coupling strength. In particular, donorlike states originating from heptagonal rings are found to give a very narrow level. Interference between broad and narrow levels produces Fano-type resonant backscattering as well as resonant tunneling. Over a significantly wide energy range, almost perfect suppression of the conduction of $π^{*}$ electrons occurs, which may be regarded as filtering of particular electrons ($π$-pass filter).

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Gunn Kim, Sang Bong Lee, Tae-Suk Kim, Jisoon Ihm. 2005-05-29. Fano Resonance and Orbital Filtering in Multiply Connected Carbon Nanotubes. https://doi.org/10.1103/physrevb.71.205415

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