Intrinsic ferromagnetic axion insulator

Tay-Rong Chang^1,2*, Ni Ni³, Dan Dessau⁴

¹Physics, National Cheng Kung University, Tainan, Taiwan
²Center for Quantum Frontiers of Research & Technology (QFort), National Cheng Kung University, Tainan, Taiwan
³Physics and Astronomy, University of California, Los Angeles, CA, USA
⁴Physics, University of Colorado, Boulder, CO, USA

* Presenter:Tay-Rong Chang, email:u32trc00@phys.ncku.edu.tw

In the past decade, the correlation between symmetry and topology have taken the central stage of modern physics. It has attracted intensive research interests in condensed matter physics and materials science since the discovery of various topological materials such as quantum spin Hall insulators, 3D topological insulators, and inversion-symmetry breaking Weyl semimetals. Despite tremendous progress, the majority of known topological materials are nonmagnetic while the novel magnetic topological materials have remains elusive. In this work, we predict the existence of an intrinsic ferromagnetic axion state in the magnetic topological material MnBi₈Te₁₃ for the first time [1]. Our finding provides a superior material realization to explore zero-field QAH effect, quantized topological magnetoelectric effect, and associated phenomena.

[1] Chaowei Hu et al., Realization of an intrinsic ferromagnetic topological state in MnBi₈Te₁₃, Science Advances 6, eaba4275 (2020).

Keywords: Topological materials, first-principles calculations, band structures, axion insulator