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Updated: Aug 6, 2026
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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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Simultaneous two-color absorption dynamics in the van der Waals ferromagnet Fe3GeTe2
Nele Stetzuhn, Emmanuelle Jal1, Juliette Dubois1
1Sorbonne Université, CNRS, Laboratoire de Chimie Physique - Matière et Rayonnement, LCPMR, F-75005 Paris, France.
Structural Dynamics (Melville, N.Y.)
|August 5, 2026
Summary
Researchers studied ultrafast electron and spin dynamics in iron-germanium-telluride (FGT) using advanced X-ray techniques. They observed surprisingly slow carrier relaxation in this 2D material, crucial for future spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Understanding the response of 2D materials to external stimuli is crucial for their integration into future electronic devices.
- Iron-germanium-telluride (FGT) is a metallic van der Waals material with potential applications in spintronics.
- Investigating electron and spin dynamics provides fundamental insights into material properties.
Purpose of the Study:
- To investigate the electron and spin dynamics in FGT after ultrafast optical excitation in its paramagnetic state.
- To understand the energy-dependent charge dynamics and carrier relaxation times.
- To explore the potential for light-induced ferromagnetic order above the Curie temperature.
Main Methods:
- Utilized a zone plate streaking technique with extreme ultraviolet (XUV) probing energies tuned to Fe M2,3 and Te N4,5 absorption edges.
- Employed static X-ray absorption spectroscopy (XAS) at elemental edges to analyze material composition and electronic states.
- Conducted time-resolved X-ray magnetic circular dichroism (TR-XMCD) measurements at room temperature.
Main Results:
- Observed surprisingly slow carrier relaxation times, up to (2.2 ± 0.6) ps in Te and exceeding several picoseconds in Fe, contradicting typical metallic behavior.
- Static XAS revealed a double feature at the Fe M2,3 edge, attributed to distinct Fe sites and a surface oxidized layer.
- TR-XMCD measurements did not provide clear evidence for light-induced ferromagnetic order above the Curie temperature (Tc).
Conclusions:
- The study reveals complex charge and spin dynamics in FGT, highlighting slow carrier relaxation as a key characteristic.
- The findings suggest that time-resolved signals may originate from a mixture of pristine and oxidized Fe species.
- This research provides foundational knowledge for advancing 2D spintronics and developing novel electronic devices based on FGT.
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