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Shell filling in closed single-wall carbon nanotube quantum dots

David H. Cobden·Jesper Nygard
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Abstract

We observe two-fold shell filling in the spectra of closed one-dimensional quantum dots formed in single-wall carbon nanotubes. Its signatures include a bimodal distribution of addition energies, correlations in the excitation spectra for different electron number, and alternation of the spins of the added electrons. This provides a contrast with quantum dots in higher dimensions, where such spin pairing is absent. We also see indications of an additional fourfold periodicity indicative of K-K' subband shells. Our results suggest that the absence of shell filling in most isolated nanotube dots results from disorder or nonuniformity.

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David H. Cobden, Jesper Nygard. 2001-12-18. Shell filling in closed single-wall carbon nanotube quantum dots. https://doi.org/10.1103/physrevlett.89.046803

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