Mott Transitions: A Brief Review

• Published in: Advanced quantum technologies (Online) 2024-10, Vol.7 (12), p.n/a
• Main Authors: Laad, Mukul S., Craco, Luis
• Format: Article
• Language: English
• Subjects: bad metal; mott insulators; mott transitions; non‐Fermi liquid; orbital‐only quantum compass model
• ISSN: 2511-9044; 2511-9044
• DOI: 10.1002/qute.202200186

This short review provides an overview of some aspects of the current understanding of Mott insulators and Mott metal‐insulator transitions. The development of this field is traced, from earliest classical views to the state‐of‐the‐art picture based on methods of quantum field theory. A quasi‐local view point, characterizing “pure” Mott physics, throughout this article is focused on. Following an extensive discussion on Mott transitions in one‐ and multi‐orbital Hubbard models, progress is reviewed in first‐principles correlation‐based approaches in achieving a quantitative description of insulator‐metal transitions in two celebrated Mott materials. Building thereupon, success of such approaches in providing microscopic justification for the famed Mott criterion, as well as in the attempts to model emerging devices is reviewed briefly. The study is concluded with a discussion of a class of Mott insulators modeled by the Kugel‐Khomskii model, and discuss how progress in the understanding of novel quantum liquid‐crystal‐like order provides an attractive opportunity to gain insight into topologically ordered states and topological‐to‐trivial phase transitions for certain quantum spin models in terms of a dual description in terms of Landau‐like symmetry breaking. The seventy‐five year old phenomenon of the Mott transition between a metal and an insulator is one of the hottest contemporary topics in condensed matter physics. It's fundamental physics increasingly manifests in high‐Tc superconductivity, topological order, fractionalization and new, emerging developments. On the applied front, a range of futuristic technologies, based on this phenomenon, seem poised to revolutionize future devices. This short review deals with our current understanding of the pure Mott phenomenon, and places it in the context of historical approaches that have endured the test of time. The figure shows the spectacular Mott transition in VO2, a system that has acquired prominence in this decade as a Motttronic material for ultrafast switches, topological transistors, MOSFETs and smart windows (see text).