Topological Quantum Matter to Topological Phase Conversion: Fundamentals, Materials, Physical Systems for Phase Conversions, and Device Applications

TL;DR

This paper reviews the fundamentals, materials, physical systems, and device applications related to topological phase conversions in quantum materials, emphasizing the importance of understanding and controlling topological properties for technological advancements.

Contribution

It provides a comprehensive overview of topological phases, their conversion mechanisms, and potential physical systems, addressing challenges in device integration and control of topological states.

Findings

Identification of key factors influencing topological phase transitions

Analysis of physical systems enabling phase conversions

Discussion of potential device applications of topological materials

Abstract

The spin-orbit coupling field, an atomic magnetic field inside a Kramer's system, or discrete symmetries can create a topological torus in the Brillouin Zone and provide protected edge or surface states, which can contain relativistic fermions, namely, Dirac and Weyl Fermions. The topology-protected helical edge or surface states and the bulk electronic energy band define different quantum or topological phases of matters, offering an excellent prospect for some unique device applications. Device applications of the quantum materials rely primarily on understanding the topological properties, their mutual conversion processes under different external stimuli, and the physical system for achieving the phase conversion. There have been tremendous efforts in finding new topological materials with exotic topological phases. However, the application of the topological properties in devices is still limited due to the slow progress in developing the physical structures for controlling the topological phase conversions. Such control systems often require extreme tuning conditions or the fabrication of complex multi-layered topological structures. This review article highlights the details of the topological phases, their conversion processes, along with their potential physical systems, and the prospective application fields. A general overview of the critical factors for topological phases and the materials properties are further discussed to provide the necessary background for the following sections.