One-dimensional moiré superlattices and flat bands in collapsed chiral carbon nanotubes

We demonstrate that one-dimensional moiré patterns, analogous to those found in twisted bilayer graphene [1, 2], can arise in collapsed chiral carbon nanotubes. Resorting to a combination of approaches, namely, molecular dynamics to obtain the relaxed geometries and tight-binding calculations validated against ab initio modeling, we find that magic angle physics occur in collapsed carbon nanotubes [3]. Velocity reduction, flat bands and localization in AA regions with diminishing moiré angle are revealed, showing a magic angle close to 1°. From the spatial extension of the AA regions and the width of the flat bands, we estimate that many-body interactions in these systems are stronger than in twisted bilayer graphene. Chiral collapsed carbon nanotubes stand out as promising candidates to explore many-body effects and superconductivity in low dimensions, emerging as the one-dimensional analogues of twisted bilayer graphene.

[1] Y. Cao et al. Nature 556, 43–50 (2018).
[2] Y. Cao et al. Nature 556, 80–84 (2018).
[3] O. Arroyo-Gascón, R. Fernández-Perea, E. Suárez Morell, C. Cabrillo and L. Chico. Nano Lett. 20, 7588–7593 (2020).