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arXiv:2306.15985 · Physical review. B./Physical review. B

Collective tunneling of a Wigner necklace in carbon nanotubes

Dominik Szombathy, Miklós Antal Werner, Cătălin Paşcu Moca, Örs Legeza, Assaf Hamo, Shahal Ilani, Gergely Zaránd

Published Jun 28, 2024• 1 citation
arXivHTMLPDF

Abstract

The collective tunneling of a Wigner necklace---a crystal-like state of a small number of strongly interacting electrons confined to a suspended nanotube and subject to a double-well potential---is theoretically analyzed and compared with experiments in Shapir et al. [Science 364, 870 (2019)]. Density matrix renormalization group computations, exact diagonalization, and instanton theory provide a consistent description of this very strongly interacting system, and show good agreement with experiments. Experimentally extracted and theoretically computed tunneling amplitudes exhibit a scaling collapse. Collective quantum fluctuations renormalize the tunneling, and substantially enhance it as the number of electrons increases.

DOI
10.1103/physrevb.109.245139

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