Related Experiment Video
Updated: Aug 2, 2025

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
Published on: July 20, 2022
Multiple Magnetic Topological Phases in the van der Waals Crystal Mn(Bi,Sb)4Se7
Jia-Yi Lin1, Zhong-Jia Chen2, Zhipeng Cao3,4
1Department of Physics, South China University of Technology, Guangzhou 510640, People's Republic of China.
Abstract:
Magnetic topological materials have drawn markedly attention recently due to the strong coupling of their novel topological properties and magnetic configurations. In particular, the MnBi2Te4/(Bi2Te3) family highlights the researches of multiple magnetic topological materials. Via first-principles calculations, we predict that Mn(Bi, Sb)4Se7, the close relatives of MnBi2Te4/(Bi2Te3) family, are topological nontrivival in both antiferromagnetic and ferromagnetic configurations. In the antiferromagnetic ground state, Mn(Bi, Sb)4Se7 are simultaneously topological insulators and axion insulators. Massless Dirac surface states emerge on the surfaces parallel to the z axis. In ferromagnetic phases, they are axion insulators. Particularly, when the magnetization direction is along the x axis, they are also topological crystalline insulators. Mirror-symmetry-protected gapless surface states exist on the mirror-invariant surfaces. Hence, the behaviors of surface states are strongly dependent on the magnetization directions and surface orientations. Our work provides more opportunities for the study of magnetic topological physics.
More Related Videos
08:55Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
09:06Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Related Concept Videos
Valence Bond Theory
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
Types Of Superconductors
VSEPR Theory and the Effect of Lone Pairs
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...