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Updated: Jul 5, 2025
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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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Atomic-Scale Visualization of Multiferroicity in Monolayer NiI2
Mohammad Amini1, Adolfo O Fumega1, Héctor González-Herrero1,2,3
1Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland.
Advanced Materials (Deerfield Beach, Fla.)
|January 19, 2024
Summary
Researchers probed multiferroic order in 2D materials using scanning tunneling microscopy. They demonstrated electric field control of multiferroic domains in monolayer nickel iodide (NiI2), enabling microscopic analysis of magnetoelectric effects.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Layered van der Waals materials exhibit unique magnetic and ferroelectric properties at the monolayer limit.
- Monolayer nickel iodide (NiI2) has been identified as the first purely two-dimensional (2D) multiferroic material.
- Characterizing multiferroicity in 2D materials requires atomic-scale experimental techniques due to limitations of bulk methods.
Purpose of the Study:
- To probe and characterize the multiferroic order in monolayer NiI2 at the atomic scale.
- To investigate the magnetoelectric coupling in NiI2 using scanning tunneling microscopy (STM).
- To establish a microscopic approach for analyzing magnetoelectric effects in 2D multiferroic materials.
Main Methods:
- Utilized scanning tunneling microscopy (STM) to probe multiferroic order.
- Employed density functional theory (DFT) calculations to support experimental findings.
- Applied external electric fields to manipulate multiferroic domains in monolayer NiI2.
Main Results:
- Demonstrated that the type-II multiferroic order in NiI2, driven by spin spiral order and spin-orbit coupling, is accessible via STM.
- Directly probed the magnetoelectric coupling by manipulating multiferroic domains with an electric field.
- Confirmed the atomic-scale characterization of multiferroic order in monolayer NiI2.
Conclusions:
- Established a novel method for analyzing magnetoelectric effects at the microscopic level in 2D materials.
- Paved the way for engineering new multiferroic orders in van der Waals materials and heterostructures.
- Highlighted the potential of NiI2 as a platform for exploring 2D multiferroicity.
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