Magneto-optical Spectroscopy of Single-Walled Carbon Nanotubes

We report the first high-field magneto-absorption and magneto-photoluminescence (PL) study on single-walled carbon nanotubes (SWNT). Magnetic fields (up to 45 Tesla) induced a large optical anisotropy as well as red shifts and splittings of the chirality-assigned [1] spectral peaks. Detailed analysis of the data shows that the observed changes are consistent with the theoretically predicted magnetic field dependant alignment of nanotubes due to their magnetic properties [2] as well as theoretically predicted magnetic field induced dramatic changes in optical absorption and bandgaps of SWNTs [3] due to the Aharonov-Bohm effect. This work was supported by the Robert A. Welch Foundation, Texas Advanced Technology Program, and NSF DMR-0134058. 1. S. M. Bachilo et al., Science 298, 2361 (2002). 2. H. Ajiki and T. Ando, J. Phys. Soc. Jpn. 62, 2470 (1993). 3. H. Ajiki and T. Ando, J. Phys. Soc. Jpn. 62,1255 (1993).