Collective tunneling of a Wigner necklace in carbon nanotubes

TL;DR

This paper theoretically analyzes the collective tunneling behavior of a Wigner necklace in carbon nanotubes, demonstrating how strong interactions and quantum fluctuations influence tunneling amplitudes, with results aligning well with experimental data.

Contribution

It introduces a comprehensive theoretical framework combining RDMRG, exact diagonalization, and instanton theory to describe collective tunneling in strongly interacting electron systems in nanotubes, matching experimental observations.

Findings

Tunneling amplitudes exhibit a scaling collapse.

Quantum fluctuations significantly enhance tunneling with more electrons.

Theoretical results agree well with experimental data.

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 \emph{et al.}, Science {\bf 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.