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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
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A Distinct Spin Structure and Giant Baromagnetic Effect in MnNiGe Compounds with Fe-Doping
Feiran Shen1,2, Houbo Zhou1,2, Fengxia Hu1,2,3
1Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Journal of the American Chemical Society
|May 3, 2021
Summary
We discovered a new antiferromagnetic spin structure in Fe-doped MnFeNiGe that transforms into a ferromagnetic state under pressure. This pressure-induced spin evolution exhibits a significant baromagnetic effect, promising for sensor applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- Spin structure in magnetic systems arises from competing exchange couplings.
- Pressure can alter interatomic distances and electronic structure, leading to spin evolution and the baromagnetic effect (BME).
- The BME has potential applications in sensors and actuators.
Purpose of the Study:
- To report a new spin structure in Fe-doped Mn0.87Fe0.13NiGe.
- To investigate pressure-driven spin structure evolution and its associated baromagnetic effect.
- To provide theoretical support for the observed phenomena.
Main Methods:
- Neutron powder diffraction (NPD) under in situ hydrostatic pressure and magnetic field.
- First-principles calculations.
Main Results:
- A new cycloidal spiral antiferromagnetic (CyS-AFMb) spin structure was identified in Fe-doped Mn0.87Fe0.13NiGe.
- Pressures above 4 kbar induced a transformation to a 45°-conical spiral ferromagnetic (45°-CoS-FMa) configuration.
- The transformation resulted in a shortened magnetic moment (by 22%) and an enhanced BME.
- First-principles calculations supported the pressure-induced spin structure evolution and broadened 3d bandwidth of Mn(Fe) atoms.
Conclusions:
- The study reveals a novel pressure-induced spin structure evolution in Fe-doped MnFeNiGe.
- The observed enhanced baromagnetic effect has significant implications for developing advanced magnetic sensors and actuators.
- Theoretical calculations confirm the mechanism behind the enhanced BME and spin structure transformation.
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