Topological Insulator Materials

TL;DR

This review comprehensively covers the basic theory, material properties, discovery history, synthesis techniques, and transport phenomena of topological insulator materials, highlighting their potential for revealing new quantum effects.

Contribution

It provides a pedagogical overview of topological insulators, summarizes all known materials as of 2013, and discusses methods to confirm their topological nature and analyze their unique transport properties.

Findings

Identification of surface Dirac fermions through quantum oscillations

Summary of topological insulator materials discovered up to 2013

Discussion of synthesis techniques and defect chemistry

Abstract

Topological insulators represent a new quantum state of matter which is characterized by peculiar edge or surface states that show up due to a topological character of the bulk wave functions. This review presents a pedagogical account on topological insulator materials with an emphasis on basic theory and materials properties. After presenting a historical perspective and basic theories of topological insulators, it discusses all the topological insulator materials discovered as of May 2013, with some illustrative descriptions of the developments in materials discoveries in which the author was involved. A summary is given for possible ways to confirm the topological nature in a candidate material. Various synthesis techniques as well as the defect chemistry that are important for realizing bulk-insulating samples are discussed. Characteristic properties of topological insulators are discussed with an emphasis on transport properties. In particular, the Dirac fermion physics and the resulting peculiar quantum oscillation patterns are discussed in detail. It is emphasized that proper analyses of quantum oscillations make it possible to unambiguously identify surface Dirac fermions through transport measurements. The prospects of topological insulator materials for elucidating novel quantum phenomena that await discovery conclude the review.