Epitaxial stabilization of Sr3Ir2O7 thin films

TL;DR

This paper demonstrates the successful epitaxial growth of Sr3Ir2O7 thin films by mapping the thermodynamic conditions, expanding the synthesis window, and enabling the study of its unique magnetic properties.

Contribution

It introduces a method to stabilize Sr3Ir2O7 thin films through thermodynamic mapping, facilitating exploration of its exotic magnetic phenomena.

Findings

Expanded the growth window for Sr3Ir2O7 thin films

Mapped the relation between crystal structure and gas pressure

Provided a new approach to stabilize metastable materials

Abstract

Ruddlesden-popper type Srn+1IrnO3n+1 compound is a major focus of condensed matter physics where the subtle balance between electron-electron correlation, spin-orbit interaction and crystal field effect brings a host of emergent phenomena. While it is understandable that a canted antiferromagnetic (AFM) insulating state with an easy-plane anisotropy is developed in Sr2IrO4 as the 2D limit of the series, it is intriguing that bilayer Sr3Ir2O7, with slightly higher effective dimensionality, stabilizes c-axis collinear antiferromagnetism. This also renders Sr3Ir2O7 as a unique playground to study exotic physics near a critical spin transition point. However, the epitaxial growth of the Sr3Ir2O7 is still a challenging task because of the narrow growth window. In our research, we have studied the thermodynamic process during synthesis of Sr3Ir2O7 thin films. We successfully expanded the synthesis window by mapping out the relation between the thin film sample crystal structure and gas pressure. Our work thus provides a more accessible avenue to stabilize metastable materials.