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Large orbital magnetic moments in carbon nanotubes generated by resonant transport

Naoto Tsuji·Shigehiro Takajo·Hideo Aoki
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Abstract

The nonequilibrium Green's function method is used to study the ballistic transport in metallic carbon nanotubes when a current is injected from the electrodes with finite bias voltages. We reveal, both analytically and numerically, that large loop currents circulating around the tube are induced, which come from a quantum mechanical interference and are much larger than the current along the tube axis when the injected electron is resonant with a time-reversed pair of degenerate states, which are, in fact, inherent in the zigzag and chiral nanotubes. This results in large orbital magnetic moments, making the nanotube a molecular solenoid.

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Naoto Tsuji, Shigehiro Takajo, Hideo Aoki. 2007-04-20. Large orbital magnetic moments in carbon nanotubes generated by resonant transport. https://doi.org/10.1103/physrevb.75.153406

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