Non-unitary multiorbital superconductivity from competing interactions in Dirac materials

TL;DR

This paper demonstrates that competing interactions in multiorbital Dirac materials can stabilize non-unitary superconducting states, revealing a new mechanism for unconventional superconductivity driven by charge order interplay.

Contribution

It introduces a novel mechanism where competing interactions induce non-unitary multiorbital superconductivity in Dirac materials, supported by both Ginzburg-Landau theory and microscopic solutions.

Findings

Competing interactions lead to non-unitary superconductivity.

Charge order interplay promotes multiorbital non-unitary states.

The mechanism is validated through microscopic self-consistent solutions.

Abstract

Unconventional superconductors represent one of the most intriguing quantum states of matter. In particular, multiorbital systems have the potential to host exotic non-unitary superconducting states. While the microscopic origin of non-unitarity is not yet fully solved, competing interactions are suggested to play a crucial role in stabilizing such states. The interplay between charge order and superconductivity has been a recurring theme in unconventionally superconducting systems, ranging from cuprate-based superconductors to dichalcogenide systems and even to twisted van der Waals materials. Here, we demonstrate that the existence of competing interactions gives rise to a non-unitary superconducting state. We show that the non-unitarity stems from a competing charge-ordered state whose interplay with superconductivity promotes a non-trivial multiorbital order. We establish this mechanism both from a Ginzburg-Landau perspective, and also from a fully microscopic selfconsistent solution of a multiorbital Dirac material. Our results put forward competing interactions as a powerful mechanism for driving non-unitary multiorbital superconductivity.