Review on ferroelectric/polar metals

TL;DR

This review explores the history, mechanisms, design strategies, and future prospects of ferroelectric and polar metals, emphasizing their potential for novel applications despite their seemingly incompatible properties.

Contribution

It provides a comprehensive overview of ferroelectric/polar metals, highlighting recent discoveries, mechanisms, and design approaches that advance understanding and development in this field.

Findings

Discovery of unambiguous polar metal LiOsO3

Demonstration of switchable ferroelectric metal WTe2

Summary of design strategies for ferroelectric/polar metals

Abstract

The possibility of reconciliation between seemingly mutually exclusive properties in one system can not only lead to theoretical breakthroughs but also potential novel applications. The research on the coexistence of two purportedly contra-indicated properties, ferroelectricity/polarity and conductivity, proposed by Anderson and Blount over 50 years ago was recently revitalized by the discovery of the first unambiguous polar metal LiOsO3 and further fueled by the demonstration of the first switchable ferroelectric metal WTe2. In this review, we first discuss the reasons why the coexistence of ferroelectricity/polarity and conductivity have been deemed incompatible, followed by a review on the history of ferroelectric/polar metals. Secondly, we review the important milestones along with the corresponding mechanisms for the ferroelectric/polar metallic phases in these materials. Thirdly, we summarize the design approaches for ferroelectric/polar metals. Finally, we discuss the future prospects and potential applications of ferroelectric/polar metals.