Related Experiment Video
Updated: Feb 11, 2026
10:06
Fabrication and Application of Rose Bengal-chitosan Films in Laser Tissue Repair
Published on: October 23, 2012
12.7K
Laser-Rewriteable Ferromagnetism at Thin-Film Surfaces
Jonathan Ehrler1,2, Miao He3, Maxim V Shugaev3
1Helmholtz-Zentrum Dresden-Rossendorf, Institut für Ionenstrahlphysik und Materialforschung , Bautzner Landstrasse 400 , D-01328 Dresden , Germany.
ACS Applied Materials & Interfaces
|April 18, 2018
Summary
Ultrafast laser pulses reversibly switch ferromagnetism in Fe60Al40 alloys by controlling chemical order-disorder phase transitions. This enables optical control over magnetic properties for advanced data storage.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Optical manipulation of magnetism is crucial for next-generation data storage.
- Current methods focus on switching magnetization direction, not ferromagnetism itself.
Purpose of the Study:
- To demonstrate reversible optical switching of ferromagnetism in Fe60Al40 alloys.
- To exploit laser-induced chemical order-disorder phase transitions for magnetic control.
Main Methods:
- Using ~100 fs laser pulses to induce reversible order-disorder transitions in Fe60Al40.
- Investigating the role of surface supercooling and resolidification dynamics.
- Employing simulations to understand the underlying mechanisms.
Main Results:
- Laser pulses above a threshold fluence induce a nonferromagnetic B2 to ferromagnetic A2 structure transition.
- Lower-fluence laser pulses reverse the process, restoring the B2 structure and erasing ferromagnetism.
- The transition is governed by laser-fluence-dependent surface supercooling and limited vacancy diffusion.
Conclusions:
- Ultrafast lasers can reversibly control ferromagnetism in bimetallic alloys via atomic rearrangements.
- This approach offers a nonvolatile and optically controllable method for magnetic switching.
- Potential applications in advanced magnetic data storage technologies.
Related Concept Videos
01:31Ferromagnetism
3.2K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
3.2K
01:16Surface Tension and Surface Energy
3.3K
When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
3.3K
01:14Wood Surfacing
365
Wood surfacing is a critical finishing process designed to smoothen the wood surface, enhance its dimensional accuracy, and make handling safer. This process compensates for potential shrinkage during the seasoning phase by marginally increasing the wood dimensions before surfacing. It also helps correct some distortions that may occur as the wood dries.
The equipment used in the surfacing process is a plane equipped with rotating blades. This tool efficiently smoothens the wood surface and can...
The equipment used in the surfacing process is a plane equipped with rotating blades. This tool efficiently smoothens the wood surface and can...
365
01:21Cell-surface Signaling
54.6K
Hormones—or any molecule that binds to a receptor, known as a ligand—that are lipid-insoluble (water-soluble) are not able to diffuse across the cell membrane. In order to be able to affect a cell without entering it, these hormones bind to receptors on the cell membrane. When a first messenger, a hormone, binds to a receptor, a signal cascade is set off, causing second messengers, proteins inside the cell, to become activated, resulting in downstream effects.
54.6K
01:29Area of a Surface of Revolution
70
Surfaces of revolution are formed when a two-dimensional curve is rotated around an axis, producing a three-dimensional shape. This concept is used in engineering tasks like determining the surface area of a rocket nozzle, where precise calculations are critical for applying uniform heat-resistant coatings. When a curve is revolved about the x-axis, it sweeps out a continuous surface whose area must be calculated accurately to estimate material requirements.Approximating with Conical BandsTo...
70
01:23Surface Appendages of Archaea
685
Archaeal surface appendages are highly specialized structures essential for environmental adaptation, encompassing roles in adhesion, biofilm formation, and motility. Among these appendages, pili and archaella stand out for their distinct morphologies and functionalities, enabling archaea to thrive in diverse and often extreme environments.Pili: Adhesion and Biofilm FormationPili are filamentous structures assembled from pilin protein subunits, primarily contributing to adhesion and biofilm...
685