# Odd-Parity Superconductivity Driven by Octahedra Rotations in Iridium Oxides

## TL;DR

This paper explores how tilting oxygen octahedra in iridium oxides influences superconducting pairing symmetry, revealing a transition from d-wave to odd-parity spin-triplet superconductivity driven by structural distortions.

## Contribution

It demonstrates that octahedra tilting alters Fermi surface topology and promotes odd-parity superconductivity, providing a new way to engineer triplet pairing in strongly correlated, spin-orbit coupled materials.

## Key findings

- Tilting octahedra transforms Fermi surface to a Dirac point.
- Octahedral tilting suppresses d-wave pairing.
- It induces a transition to odd-parity spin-triplet superconductivity.

## Abstract

Iridium oxides have provided a playground to study novel phases originating from spin-orbit coupling and electron-electron interactions. Among them, the d-wave singlet superconductor was proposed for electron-doped Sr$_2$IrO$_4$, containing two Ir atoms in a unit cell due to the staggered rotation of oxygen octahedra about the c-axis. It was also noted that such oxygen octahedra rotation affects electronic transports. Here we study the role of octahedra tilting away from the c-axis, in determining superconducting pairing symmetry. We show that the octahedra tilting changes the large Fermi surface to a Dirac point, which strongly suppresses the conventional d-wave pairing. Furthermore, it also promotes effective spin-triplet interactions in the strong Hubbard interaction limit, leading to a transition from the even-parity to odd-parity superconducting phase. Thus, tuning octahedra distortions can be used as a tool to engineer a spin triplet superconductor in strongly correlated systems with strong spin-orbit coupling.