About
Topological phases in correlated quantum matter are currently at the forefront of condensed matter physics research. In these materials the coupling between the charge, spin, orbital and structural degrees of freedom drives a rich electronic topology, generating a range of exotic phenomena. Magnetism in particular can play a dominant role in these systems by breaking time-reversal symmetry, which forms the foundation of some topological phases and is detrimental to others.
After introducing basic concepts in magnetism and topology, this tutorial will present an overview of the current topological materials including Weyl semimetals, line node semimetals, anomalous Hall/Chern insulator states, topological insulators, topological superconductors, and other fascinating phases. Key phenomena emergent in these systems, including giant and/or quantized anomalous Hall effects, anomalous Nernst effects, circular photogalvanic effects and other exotic responses, will be presented.
Particular emphasis will be given to kagome materials, such as the Weyl semimetal Co3Sn2S2 or the Chern insulator state in TbMn6Sn6 and Heusler materials, such as the magnetic Weyl loop semimetal Co2MnGa. This tutorial will further discuss exotic properties of magnetically-doped topological platforms, notably Cr:(Bi,Sb)2Te3, as well as heterostructures exhibiting proximity-induced magnetization, such as CrSb/(Bi,Sb)2Te3 bilayers. Interplay with superconductivity, charge density waves and other correlated order parameters will also be discussed.
Speakers
- Claudia Felser, Max Plank Institute
- M. Zahid Hasan, Princeton
- Kang Wang, University of California Los Angeles