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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Spin Spiral State at a Ferromagnetic Gd Vacuum Interface
Patrick Härtl1, Matthias Vogt1, Markus Leisegang1
1Physikalisches Institut, Experimentelle Physik II, <a href="https://ror.org/00fbnyb24">Universität Würzburg</a>, Am Hubland, 97074 Würzburg, Germany.
Physical Review Letters
|November 15, 2024
Summary
Researchers observed a 2 nm spin spiral state on the Gadolinium (Gd) surface using spin-polarized scanning tunneling microscopy. This magnetic state arises from competing exchange interactions in the Gd monolayer.
Area of Science:
- Condensed Matter Physics
- Surface Science
- Magnetism
Background:
- Layered Gadolinium (Gd) intermetallics exhibit bulk helical spin spirals and skyrmion lattices.
- Understanding surface magnetic states is crucial for novel spintronic applications.
Purpose of the Study:
- To investigate and characterize the magnetic spin state at the Gd(0001) surface.
- To elucidate the underlying mechanisms driving the observed surface magnetism.
Main Methods:
- Spin-polarized scanning tunneling microscopy (SP-STM) was employed to image the surface.
- External magnetic fields were applied to probe the magnetic nature of the observed structures.
- Density functional theory (DFT) calculations were performed to model the electronic and magnetic properties.
Main Results:
- SP-STM images revealed striped regions with a periodicity of approximately 2 nm on the Gd(0001) surface.
- These striped patterns rearranged in response to an external magnetic field, confirming their magnetic origin.
- DFT calculations indicated that competing exchange interactions within the Gd surface layer favor a chiral 2 nm conical spin spiral.
Conclusions:
- A distinct 2 nm spin spiral state exists at the Gd(0001) surface.
- This surface spin spiral arises from intrinsic properties of the Gd monolayer, influenced by inter-layer magnetic coupling.
- The findings contribute to the understanding of magnetism in low-dimensional Gadolinium systems.
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