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arXiv · 1203.5618

Emerging Dirac and Majorana fermions for carbon nanotubes with proximity-induced pairing and spiral magnetic field

Reinhold Egger·Karsten Flensberg
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Abstract

We study the low-energy bandstructure of armchair and small-bandgap semiconducting carbon nanotubes with proximity-induced superconducting pairing when a spiral magnetic field creates strong effective spin-orbit interactions from the Zeeman term and a periodic potential from the orbital part. We find that gapless Dirac fermions can be generated by variation of a single parameter. For a semiconducting tube with the field in the same plane, a non-degenerate zero mode at momentum k=0 can be induced, allowing for the generation of topologically protected Majorana fermion end states.

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Reinhold Egger, Karsten Flensberg. 2012-03-26. Emerging Dirac and Majorana fermions for carbon nanotubes with proximity-induced pairing and spiral magnetic field. https://doi.org/10.1103/physrevb.85.235462

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