arXiv subjects

Sang Bong Lee

Publications and source records attributed to Sang Bong Lee.

2 recordsLinked to original sources

arXiv2006

Electron orbital valves made of multiply connected armchair carbon nanotubes with mirror-reflection symmetry: tight-binding study

Using the tight-binding method and the Landauer-Büttiker conductance formalism, we demonstrate that a multiply connected armchair carbon nanotube with a mirror-reflection symmetry can sustain an electron current of the $π$-bonding orbital while suppress that of the $π$-antibonding orbital over a certain energy range. Accordingly, the system behaves like an electron orbital valve and may be used as a scanning tunneling microscope to probe pairing symmetry in d-wave superconductors or even orbital ordering in solids which is believed to occur in some transition-metal oxides.

cond-mat.other↗

arXiv2005

Fano Resonance and Orbital Filtering in Multiply Connected Carbon Nanotubes

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).

cond-mat.mes-hall↗