Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Atomic Nuclei: Nuclear Spin State Overview01:03

Atomic Nuclei: Nuclear Spin State Overview

809
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of...
809
Ferromagnetism01:31

Ferromagnetism

2.3K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.3K
Atomic Nuclei: Nuclear Relaxation Processes01:23

Atomic Nuclei: Nuclear Relaxation Processes

581
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis,  the precessing magnetic moments are randomly oriented around the z-axis.
581
Atomic Nuclei: Nuclear Spin State Population Distribution01:14

Atomic Nuclei: Nuclear Spin State Population Distribution

891
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
891
Colors and Magnetism03:02

Colors and Magnetism

11.3K
Color in Coordination Complexes
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...
11.3K
Atomic Nuclei: Magnetic Resonance01:05

Atomic Nuclei: Magnetic Resonance

588
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
588

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Trait Architecture of Fruit-Panicle Economic Traits in <i>Idesia polycarpa</i> and Its Implications for Breeding.

Plants (Basel, Switzerland)·2026
Same author

Polar nano-regions enable large spin Hall conductivity in metallic PtCoO<sub>2</sub>.

Nature materials·2026
Same author

Emergent One-Dimensional Charge Order at Domain Walls of Competing Charge-Density-Wave Orders.

Nano letters·2026
Same author

Unconventional magnon-mediated spin torque enabled by ferroelectric domain engineering in multiferroic BiFeO<sub>3</sub>.

Nature communications·2026
Same author

Single-Electrode High-Throughput 12-Well Array Electrochemiluminescence Imaging Sensor for Portable Parallel Dual-Color Analysis of Dual Breast Cancer Susceptibility Genes.

Analytical chemistry·2026
Same author

Targeting KAT8 alleviates vascular senescence by modulating the INHBA/TGF-β pathway.

Molecular therapy : the journal of the American Society of Gene Therapy·2025

Related Experiment Video

Updated: May 11, 2025

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
10:36

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials

Published on: January 21, 2016

10.5K

Antiferromagnetic quantum anomalous Hall effect under spin flips and flops.

Zichen Lian1, Yongchao Wang1, Yongqian Wang2,3

  • 1State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, People's Republic of China.

Nature
|April 16, 2025
PubMed
Summary

Researchers explored the antiferromagnetic quantum anomalous Hall effect in MnBi2Te4. They observed tunable quantum phase transitions and unique magnetic field effects, paving the way for topological spintronics.

More Related Videos

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
09:06

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope

Published on: March 24, 2019

8.0K
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
09:00

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

Published on: June 28, 2018

9.8K

Related Experiment Videos

Last Updated: May 11, 2025

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
10:36

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials

Published on: January 21, 2016

10.5K
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
09:06

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope

Published on: March 24, 2019

8.0K
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
09:00

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

Published on: June 28, 2018

9.8K

Area of Science:

  • Condensed Matter Physics
  • Materials Science

Background:

  • MnBi2Te4 exhibits interplay between band topology and layered antiferromagnetism, enabling exploration of topological phases.
  • Previous studies observed quantum anomalous Hall effect and axion insulator states in MnBi2Te4, but antiferromagnetic dynamics effects remain largely unexplored.

Purpose of the Study:

  • Investigate the antiferromagnetic quantum anomalous Hall effect in MnBi2Te4.
  • Explore the influence of complex spin configurations on edge state transport.
  • Understand the impact of in-plane magnetic fields on the material's properties.

Main Methods:

  • Fabrication of a 7-septuple-layer MnBi2Te4 device with an AlOx capping layer.
  • Tuning gate voltage and perpendicular magnetic field to induce quantum phase transitions.
  • Application of in-plane magnetic fields and numerical simulations.

Main Results:

  • Observed a cascade of quantum phase transitions influenced by spin configurations.
  • Found that in-plane magnetic fields enhance coercive field and surface state exchange gap, unlike ferromagnetic materials.
  • Identified spin flip and flop transitions as key mechanisms in this van der Waals antiferromagnet.

Conclusions:

  • The study reveals tunable quantum anomalous Hall effect in MnBi2Te4 driven by complex antiferromagnetic spin dynamics.
  • Peculiar magnetic field effects are attributed to inherent spin transitions in the van der Waals antiferromagnet.
  • Findings open avenues for topological antiferromagnetic spintronics applications.