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Updated: Aug 5, 2026
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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Geometric Spin Rotation in Triangular Antiferromagnets
Grigor Adamyan1,2, Bastián Pradenas1,3, Boris Ivanov1,4
1Johns Hopkins University, William H. Miller III Department of Physics and Astronomy, Baltimore, Maryland 21218, USA.
Physical Review Letters
|July 26, 2026
Summary
A novel geometric phenomenon transforms the ground state of a triangular Heisenberg antiferromagnet using spin waves. This discovery offers new ways to control magnetic order with potential applications in other frustrated magnets and physical systems.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Geometric Phases
Background:
- Degenerate Goldstone modes are fundamental excitations in systems with broken symmetry.
- Antiferromagnetic materials, particularly Heisenberg antiferromagnets, exhibit complex spin dynamics.
- Understanding the interplay between spin waves and magnetic order is crucial for materials science.
Purpose of the Study:
- To describe a geometric phenomenon involving traveling waves and ground state transformation.
- To investigate the effect of circularly polarized spin waves on a triangular Heisenberg antiferromagnet.
- To explore the potential for controlling antiferromagnetic order using spin waves.
Main Methods:
- Analysis of a traveling wave composed of degenerate Goldstone modes.
- Application of circularly polarized spin waves to a triangular Heisenberg antiferromagnet.
- Exact solution of nonlinear equations of motion to determine the accumulated rotation.
Main Results:
- A traveling wave transforms the ground state of the antiferromagnet.
- The accumulated spin rotation is identified as a geometric phase.
- An analogy is drawn between the magnetic order parameter's motion and a wobbling coin.
Conclusions:
- The observed phenomenon provides a new method for controlling antiferromagnetic order via spin waves.
- This geometric effect may be applicable to other frustrated magnets.
- The findings could extend to diverse physical systems with noncommuting broken-symmetry generators.
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