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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Polymorphic Spin Ordering in a Single-Crystalline Cobalt-Doped Fe3GaTe2
Woohyun Cho1, Jaehun Cha1, Yoon-Gu Kang1
1Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
ACS Nano
|November 25, 2025
Summary
Cobalt-doped Fe3GaTe2 exhibits polymorphic spin ordering, displaying three distinct magnetic states—ferromagnetic, collinear antiferromagnetic, and noncollinear antiferromagnetic—within a single crystal. This discovery offers new avenues for controlling spin states in advanced materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Single-crystalline systems typically exhibit a unique spin ordering below a critical temperature.
- Van der Waals magnets offer control over spin states through interlayer exchange interactions.
- Controlling multiple magnetic states in a single material is a significant challenge.
Purpose of the Study:
- To investigate the magnetic properties of cobalt-doped Fe3GaTe2 ((Co, Fe)3GaTe2).
- To explore the phenomenon of multiple magnetic phase transitions in a single material.
- To understand the role of doping in modulating magnetic interactions and spin ordering.
Main Methods:
- Synthesis of single-crystalline (Co, Fe)3GaTe2.
- Magnetic force microscopy for visualizing spin ordering.
- First-principles calculations to model electronic structure.
- Circular dichroism angular photoemission spectroscopy (CDAS) to probe electronic states.
Main Results:
- Observed three distinct magnetic states: ferromagnetic, collinear antiferromagnetic, and noncollinear antiferromagnetic ordering in (Co, Fe)3GaTe2.
- Identified three critical temperatures: Curie temperature (Tc = 210 K) and two Néel temperatures (TN1 = 110 K, TN2 = 30 K).
- Demonstrated polymorphic spin ordering within the same lattice system due to modulated interlayer magnetic interactions.
Conclusions:
- Co-doping in Fe3GaTe2 enables polymorphic spin ordering, a novel phenomenon in layered magnets.
- The material exhibits significant changes in topological band structure and Berry curvature across magnetic transitions.
- Findings provide a new platform for exploring complex spin textures and their control in van der Waals materials.
Keywords:
2D materialsanomalous Hall effectcircular dichroism angle-resolved photoemission spectroscopyco-doped Fe3GaTe2magnetismpolymorphismMore Related Videos
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