Related Experiment Video
Updated: Apr 13, 2026

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Element-Selective Probing of Ultrafast Ferromagnetic-Antiferromagnetic Order Dynamics in Fe/CoO Bilayers
Chowdhury S Awsaf1, Sangeeta Thakur1, Markus Weißenhofer1,2
1Freie Universität Berlin, Institut für Experimentalphysik, Arnimallee 14, 14195 Berlin, Germany.
Abstract:
The ultrafast magnetization dynamics of an epitaxial Fe/CoO bilayer on Ag(001) is examined in an element-resolved way by resonant soft-x-ray reflectivity. The transient magnetic linear dichroism at the Co L_{2} edge and the magnetic circular dichroism at the Fe L_{3} edge measured in reflection in a pump-probe experiment with 120 fs temporal resolution show the loss of antiferromagnetic and ferromagnetic order in CoO and Fe, respectively, both within 300 fs after excitation with 60 fs light pulses of 800 and 400 nm wavelengths. A comparison to spin-dynamics simulations using an atomistic spin model shows that direct energy transfer from the laser-excited electrons in Fe to the magnetic moments in CoO provides the dominant demagnetization channel in the case of 800-nm excitation.
Related Concept Videos
Ferromagnetism
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
Valence Bond Theory
Magnetic Susceptibility and Permeability
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...

