# Dimensionality-strain phase diagram of strontium iridates

## TL;DR

This study uses first-principles calculations to map how dimensionality and strain influence electronic and magnetic phase transitions in strontium iridate superlattices, revealing complex behavior beyond simple models.

## Contribution

It provides a detailed phase diagram showing how strain and dimensionality control magnetic and electronic states in iridate superlattices, incorporating effects beyond local approximations.

## Key findings

- Identified two controllable transitions: spin-flop and insulator-metal.
- Demonstrated the disruption of the $J_{eff}=1/2$ state under certain conditions.
- Mapped the phase diagram relating strain, dimensionality, and electronic states.

## Abstract

The competition between spin-orbit coupling, bandwidth ($W$) and electron-electron interaction ($U$) makes iridates highly susceptible to small external perturbations, which can trigger the onset of novel types of electronic and magnetic states. Here we employ {\em first principles} calculations based on density functional theory and on the constrained random phase approximation to study how dimensionality and strain affect the strength of $U$ and $W$ in (SrIrO$_3$)$_m$/(SrTiO$_3$) superlattices. The result is a phase diagram explaining two different types of controllable magnetic and electronic transitions, spin-flop and insulator-to-metal, connected with the disruption of the $J_{eff}=1/2$ state which cannnot be understood within a simplified local picture.