HiSORセミナー
Magnetism and Topology: From Magnetic Topological Insulators to the Emerging Altermagnets
日時 2025年12月18日 （木） 14：00～15：00
場所 オンライン(Zoom形式)
https://us02web.zoom.us/j/83260922569?pwd=3wSIh06NCyexRGbPExREHjVNyotTvb.1
ミーティング ID: 832 6092 2569
パスコード: 571300
講師 Mohit Mudgal
(Indian Institute of Technology Kanpur)
The study of new quantum states of matter, particularly those emerging from the interplay between nontrivial band topology and magnetism, is a major focus in condensed matter physics due to phenomena like the quantum anomalous Hall effect and axion dynamics [1]. This talk is divided into two parts. In the first part of the talk, I will discuss the magnetotransport and ARPES study of magnetic topological insulators, MnSb8Te13 and MnSb12Te19, part of the MnSb2nTe3n+1 family, which is known for highlighting the interplay between magnetism and topology. DFT calculations predict that MnSb8Te13 behaves as an axion insulator with surface states that depend on the termination, earning it the term 'half-magnetic topological insulator.' However, magnetic measurements suggest that the sample exhibits weak ferromagnetism due to Mn deficiency and disorder [2]. On the other hand, MnSb12Te19 exhibits clear ferromagnetic behavior, with the anomalous Hall effect observed when a magnetic field is applied along the c-axis [3]. Additionally, I will discuss the non-trivial topological nature of PbBi6Te10 through ARPES and transport studies [4].
In the second part of the talk, I will explore the world of new magnetic phases, known as altermagnets. I will discuss the recent studies, challenges, and potential solutions to experimentally identifying the Altermagnets [5].
[1] Gu et. al., Nat. Comms. 12, 3524 (2021).
[2] Mudgal et. al., Phys. Rev. B. 110, 045124 (2024).
[3] Mudgal et. al., J. Phys.: Condens. Matter 36, 50LT01 (2024).
[4] Mudgal et. al., Appl. Phys. Lett. 127, 153101 (2025).
[5] Song et. al., Nat Rev Mater 10, 473–485 (2025).
問合せ先 出田真一郎（放射光科学研究所）
