Correlated Electron Materials and Field Effect Transistors for Logic: A Review

TL;DR

This review discusses how correlated electron materials exhibit phase transitions useful for next-generation field-effect transistors, highlighting recent experimental techniques and future research prospects in oxide electronics.

Contribution

It provides a comprehensive overview of metal-insulator transition mechanisms and their application in field-effect transistors using correlated oxides, emphasizing novel gating methods and future directions.

Findings

Correlated electron systems can undergo phase transitions useful for logic devices.

Electrostatic gating techniques like ionic liquid gating enable large carrier densities.

Correlated oxides show promise for future electronic applications.

Abstract

Correlated electron systems are among the centerpieces of modern condensed matter sciences, where many interesting physical phenomena, such as metal-insulator transition and high-Tc superconductivity appear. Recent efforts have been focused on electrostatic doping of such materials to probe the underlying physics without introducing disorder as well as to build field-effect transistors that may complement conventional semiconductor metal-oxide-semiconductor field effect transistor (MOSFET) technology. This review focuses on metal-insulator transition mechanisms in correlated electron materials and three-terminal field effect devices utilizing such correlated oxides as the channel layer. We first describe how electron-disorder interaction, electron-phonon interaction and/or electron correlation in solids could modify the electronic properties of materials and lead to metal-insulator transitions. Then we analyze experimental efforts toward utilizing these transitions in field effect transistors and their underlying principles. It is pointed out that correlated electron systems show promise among these various materials displaying phase transitions for logic technologies. Furthermore, novel phenomena emerging from electronic correlation could enable new functionalities in field effect devices. We then briefly review unconventional electrostatic gating techniques, such as ionic liquid gating and ferroelectric gating, which enables ultra large carrier accumulation density in the correlated materials which could in turn lead to phase transitions. The review concludes with a brief discussion on the prospects and suggestions for future research directions in correlated oxide electronics for information processing.