Interface magnetism (FWIN-G)
Our group is investigating magnetic effects at interfaces between different structures. Those structures are created by means of thin film deposition and ion irradiation. One example are metallic multilayers where the magnetic properties are locally taylored by ion irradiation or the magnetic doping of non-magnetic materials. The interface-magnetism-group is working in different projects which are partially funded by external sources (see below).
- MACHO (Magnetic anisotropies in Cobalt heterostructures induced by oxidation - with IFJ Cracow)
- MEMRIOX (Memristive oxides - HGF Virtual Institute VH-VI-422)
- DETI.2 (Defects in magnetic TiO2 - HRJRG-314)
- Spin tranfer torque effects in metallic multilayers and tunnel structures (BMBF, FKZ 13N10144)
- Embedded magnetic nanoparticles (DFG, PO1275/2-1)
- Magnetic clusters in semiconductors
- Magnetic multilayers
Are you interested in taking part in our scientific work, e.g. as a students lab assistant of for a Bachelor/Master thesis? Please also contact email@example.com directly.
Or maybe you are generally interested in
- A Bachelor or Master thesis or a position as a student assistent in our group?
- A Bachelor, Diploma, Master or PhD-thesis at our institute
- Our summer student program?
- Laser-Rewriteable Ferromagnetism at Thin-Film Surfaces
Ehrler, Jonathan; He, Miao; Shugaev, Maxim V.; Polushkin, Nikolay I.; Wintz, Sebastian; Liersch, Vico; Cornelius, Steffen; Hubner, Rene; Potzger, Kay; Lindner, Juergen; Fassbender, Juergen; Unal, Ahmet A.; Valencia, Sergio; Kronast, Florian; Zhigilei, Leonid V.; Bali, Rantej
ACS APPLIED MATERIALS & INTERFACES Volume: 10 Issue: 17 Pages: 15232-15239 2018
Abstract: Manipulation of magnetism using laser light is considered as a key to the advancement of data storage technologies. Until now, most approaches seek to optically switch the direction of magnetization rather than to reversibly manipulate the ferromagnetism itself. Here, we use, similar to 100 fs laser pulses to reversibly switch ferromagnetic ordering on and off by exploiting a chemical order disorder phase transition in Fe60Al40, from the B2 to the A2 structure and vice versa. A single laser pulse above a threshold fluence causes nonferromagnetic B2 Fe60Al40 to disorder and form the ferromagnetic A2 structure. Subsequent laser pulsing below the threshold reverses the surface to B2 Fe60Al40, erasing the laser-induced ferromagnetism. Simulations reveal that the order disorder transition is regulated by the extent of surface supercooling; above the threshold for complete melting throughout the film thickness, the liquid phase can be deeply undercooled before solidification. As a result, the vacancy diffusion in the resolidified region is limited and the region is trapped in the metastable chemically disordered state. Laser pulsing below the threshold forms a limited supercooled surface region that solidifies at sufficiently high temperatures, enabling diffusion-assisted reordering. This demonstrates that ultrafast lasers can achieve subtle atomic rearrangements in bimetallic alloys in a reversible and nonvolatile fashion.