Supermodulation-driven evolution of the nodal structure of bismuth-based cuprate superconductors

TL;DR

This paper investigates how intrinsic supermodulation in bismuth-based cuprate superconductors influences their electronic structure, revealing critical points where semi-Dirac nodes emerge, which could impact understanding of their superconducting properties.

Contribution

It demonstrates that supermodulation in bismuth-based cuprates leads to the formation of semi-Dirac nodes at specific critical points, a phenomenon previously associated mainly with twisted cuprates.

Findings

Semi-Dirac nodes form at two critical points as supermodulation potential increases.

Bi2212 and Bi2201 are predicted to exhibit these critical points.

Implications for the electronic properties of cuprates are discussed.

Abstract

Recent work has shown novel properties of twisted cuprates. In this paper, I point out that related phenomena occur intrinsically in bismuth-based cuprate superconductors due to the presence of the BiO supermodulation. As the ratio of the supermodulation potential to the superconducting energy gap increases, two critical points are found where semi-Dirac nodes form (that is, that have quadratic dispersion in one direction and liner dispersion in the orthogonal direction). The first critical point should be realized in Bi2212, the second in Bi2201. Implications of these findings are discussed.