Emergent phenomena at oxide interfaces studied with standing-wave photoelectron spectroscopy

TL;DR

This review discusses how standing-wave photoelectron spectroscopy is used to study complex-oxide interfaces, revealing emergent phenomena like metal-insulator transitions and interfacial magnetism with high resolution.

Contribution

It provides a comprehensive overview of recent applications of standing-wave photoelectron spectroscopy in probing buried oxide interfaces and their emergent properties.

Findings

Demonstrates the technique's ability to resolve buried interfaces

Highlights emergent phenomena such as 2D electron gases and ferromagnetism

Discusses advantages and future potential of the methodology

Abstract

Emergent phenomena at complex-oxide interfaces have become a vibrant field of study in the past two decades due to the rich physics and a wide range of possibilities for creating new states of matter and novel functionalities for potential devices. Electronic-structural characterization of such phenomena presents a unique challenge due to the lack of direct yet non-destructive techniques for probing buried layers and interfaces with the required Angstrom-level resolution, as well as element and orbital specificity. In this review article, we survey several recent studies wherein soft x-ray standing-wave photoelectron spectroscopy, a relatively newly developed technique, is used to investigate buried oxide interfaces exhibiting emergent phenomena such as metal-insulator transition, interfacial ferromagnetism, and two-dimensional electron gas. Advantages, challenges, and future applications of this methodology are also discussed.