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Updated: May 13, 2026
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
A magnetic glassy phase in Fe(1+y)Se(x)Te(1-x) single crystals.
1CNR-SPIN and Università di Genova, Via Dodecaneso 33, I-16146 Genova, Italy.
Summary
Investigating magnetic order in iron selenide telluride crystals reveals an antiferromagnetic phase that disorders with increasing selenium. A magnetic glassy state emerges, driven by inhomogeneities, impacting muon-spin spectroscopy and magnetometry findings.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid State Chemistry
Background:
- Understanding magnetic order in transition metal compounds is crucial for novel electronic applications.
- Iron selenide telluride (FeSeTe) systems exhibit complex magnetic phase diagrams.
- Investigating the influence of composition on magnetic properties is key to material design.
Purpose of the Study:
- To elucidate the evolution of magnetic order in Fe1+ySexTe1-x crystals.
- To determine the site of muon implantation and the origin of the local field.
- To correlate magnetic behavior with Se content and material inhomogeneities.
Main Methods:
- Ac/dc magnetometry to probe magnetic susceptibility and phase transitions.
- Muon-spin spectroscopy (µSR) to investigate local magnetic fields and dynamics.
- Self-consistent density functional theory (DFT) calculations for theoretical validation.
Main Results:
- Muons are implanted in iron-excess sites, probing dipolar fields from an antiferromagnetic (AFM) bicollinear spin arrangement.
- The long-range AFM phase disorders with increasing Se content.
- A significant glassy magnetic character is observed, diminishing at high Se concentrations, attributed to magnetic clusters.
Conclusions:
- The study clarifies the magnetic structure and its dependence on Se content in Fe1+ySexTe1-x.
- Muon-spin spectroscopy provides insights into local magnetic fields and dynamics.
- Material inhomogeneities play a critical role in establishing the observed glassy magnetic state.
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