Dynamical axion state with hidden pseudospin Chern numbers in MnBi2Te4 -based heterostructures
Abstrak
An axion is a hypothetical elementary particle which was initially postulated to solve the charge conjugation-parity problem in particle physics. Interestingly, the axion state has emerged in the effective theory of topological insulators and has attracted extensive attention in condensed matter physics. Time-reversal or inversion symmetry constrains the axion field $\ensuremath{\theta}$ to be quantized. When both the time-reversal and inversion symmetries are broken by, say, an antiferromagnetic order, the axion field $\ensuremath{\theta}$ could become unquantized and dynamical along with magnetic fluctuations, which is termed the dynamical axion field. Here, we reveal that a wide class of topological-insulator-based dynamical axion states could be distinguished from the normal-insulator-based ones by a hidden quantity derived from the pseudospin Chern number. Motivated by recent research on the ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ family of materials, we further show that such topological-insulator-based dynamical axion states can be hopefully achieved in ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$-based heterostructures, which should greatly facilitate the study of axion electrodynamics in condensed matter physics.
Topik & Kata Kunci
Penulis (8)
Huaiqiang Wang
Dinghui Wang
Zhilong Yang
M. Shi
Jiawei Ruan
D. Xing
Jing Wang
Haijun Zhang
Akses Cepat
- Tahun Terbit
- 2019
- Bahasa
- en
- Total Sitasi
- 29×
- Sumber Database
- Semantic Scholar
- DOI
- 10.1103/PhysRevB.101.081109
- Akses
- Open Access ✓