Topological superconductivity on the honeycomb lattice: Effect of normal state topology

TL;DR

This paper investigates how the topological properties of the normal state influence the emergence of topological superconductivity on the honeycomb lattice, providing a clearer understanding of their relationship.

Contribution

It introduces a method to compare superconducting instabilities in doped insulators with equalized Fermi surface effects, revealing the impact of normal state topology.

Findings

Normal state topology affects superconducting pairing tendencies.

Equalizing Fermi surface effects allows direct comparison of topological and trivial insulators.

Results provide rigorous insights into the relationship between normal state and superconducting topology.

Abstract

The search for topological superconductors is one of the most pressing and challenging questions in condensed matter and material research. Despite some early suggestions that doping a topological insulator might be a successful recipe to find topological superconductors, until today there is no general understanding of the relationship of the topology of the superconductor and the topology of its underlying normal state system. One of the major obstacles is the strong effect of the Fermi surface and its subsequent pairing tendencies within the Hubbard model framework, usually preventing a detailed comparison between different topological superconducting systems. Here we present an analysis of doped insulators - topological and trivial - where the dominant Fermi surface effects have been equalized. Our approach allows us to study and compare superconducting instabilities of different normal state systems and present rigorous results about the influence of the normal state system's topology.