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arXiv · 1303.6164

Band-edge Exciton States in a Single-walled Carbon Nanotube Revealed by Magneto-optical Spectroscopy in Ultra-high Magnetic Field

Weihang Zhou·Tatsuya Sasaki·Daisuke Nakamura·Huaping Liu·Hiromichi Kataura·Shojiro Takeyama
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Abstract

We report high field magneto-optical study on the first and second sub-band transitions of single-chirality single-walled carbon nanotubes. The ordering and relative energy splitting between bright and dark excitonic states were found to be inverse between the first and second subbands. We verified that the zero-momentum dark singlet exciton lies below the bright exciton for the first subband transitions, while for the second sub-band transitions, it was found to have higher energy than the bright excitonic state. Effect of this peculiar excitonic structure was found to manifest itself in distinctive Aharonov-Bohm splitting in ultra-high magnetic fields up to 190 T.

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Weihang Zhou, Tatsuya Sasaki, Daisuke Nakamura, Huaping Liu, Hiromichi Kataura, Shojiro Takeyama. 2013-03-25. Band-edge Exciton States in a Single-walled Carbon Nanotube Revealed by Magneto-optical Spectroscopy in Ultra-high Magnetic Field. https://doi.org/10.1103/physrevb.87.241406

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