Combining magnetism and topology: from magnetic doping to novel interfaces and intrinsic magnetic topological insulators

量子物理学・ナノサイエンス第87回特別セミナー

概要

In this talk, I will overview the developments in the field of magnetic topological insulators (MTIs) that led to the discovery of the intrinsic MTIs of the MnBi₂Te₄ family that attracts a great deal of attention nowadays. First, to describe the context in which materials such as MnBi₂Se₄ and MnBi₂Te₄ appeared in the research arena, I will discuss the magnetic doping and magnetic proximity effect approaches of introducing magnetism into a TI. Then, the two types of novel and promising interfaces involving MnBi₂Te(Se)₄ compounds will be discussed, as they are expected to show certain advantages over the latter two approaches. Next, the discovery of intrinsic MTIs of the MnBi₂Te(Se)₄ family will be overviewed. Finally, concerning current challenges of this field, we will consider in detail the issue of the Dirac point gap in the MnBi₂Te₄ topological surface state that has caused a lot of controversy recently.

• M. M. Otrokov et al., Nature 576, 416–422 (2019).
• M. Garnica, M. M. Otrokov et al., npj Quantum Materials 7, 7 (2022).

• 量子物理学・ナノサイエンス第87回特別セミナー

• 東京工業大学理学院・物理学系 ナノサイエンスを拓く量子物理学拠点　共催