Magnetism
We seek to explore and understand how energy and length scales, along with their hierarchical structure, influence magnetic order and dynamics. To achieve this, we employ a wide range of synthesis and experimental characterization techniques that allow precise control over the chemistry and atomic structure of materials. These tools enable us to study and design material interactions, such as exchange interactions and anisotropies, which directly influence magnetic ordering.
Additionally, we define the spatial dimensions over which these interactions occur by using thin film deposition, multilayer fabrication, lithography, ion beam techniques, and additive manufacturing methods. Magnetic properties vary across different length scales – atomic, nanoscale, microscale, and beyond. For example, nanostructured materials often exhibit distinct magnetic behaviours compared to bulk materials due to finite-size effects, surface-to-volume ratios, or spatial confinement.

The nanoscale pattern influences the magnetic order leading to spins pointing either up or down.
In magnetic systems, hierarchy refers to the multi-scale nature of interactions, where energy and length scales either interact or compete. At smaller scales, such as the atomic level, quantum mechanical effects dominate, whereas at larger scales, macroscopic magnetic domains or long-range order become more significant.
All these factors collectively influence the magnetic ordering in materials (for example, ferromagnetic, antiferromagnetic, etc.), as the type of order is shaped by both energy interactions and spatial considerations.
Magnetic dynamics, on the other hand, refer to the evolution of the magnetic system over time. This includes how spins respond to external stimuli such as magnetic fields or temperature changes, and the timescales over which the system reconfigures its magnetic ordering.
These core concepts have wide-ranging applications across various research and technological areas, including:
- Spintronics: Controlling magnetic order and dynamics across different energy and length scales is critical for developing efficient memory and logic devices.
- Magnetic nano- and metamaterials: Designing materials with unique behaviours at the meso- and nanoscale, influenced by energy and length-scale considerations.
- Magnetic phase transitions: Understanding how energy and spatial hierarchies drive magnetic phase transitions.
- Magnetophotonics: Exploring how magnetic materials can manipulate light and, conversely, how light can affect magnetic properties and dynamics.
Selected publications
Effect of iron layer thickness on the interlayer exchange coupling in Fe/MgO (001) superlattices
Part of Physical Review B, 2024
- DOI for Effect of iron layer thickness on the interlayer exchange coupling in Fe/MgO (001) superlattices
- Download full text (pdf) of Effect of iron layer thickness on the interlayer exchange coupling in Fe/MgO (001) superlattices
Part of Materials & design, 2024
- DOI for Stress related magnetic imaging of iron-based metallic glass produced with laser beam powder bed fusion
- Download full text (pdf) of Stress related magnetic imaging of iron-based metallic glass produced with laser beam powder bed fusion
Part of Journal of Applied Physics, 2023
- DOI for Magnetic Properties versus Interface Density in Rigid-Exchange-Coupled Amorphous Multilayers with Induced Uniaxial Anisotropy
- Download full text (pdf) of Magnetic Properties versus Interface Density in Rigid-Exchange-Coupled Amorphous Multilayers with Induced Uniaxial Anisotropy
Magnetic and all-optical switching properties of amorphous TbxCo100-x alloys
Part of Physical Review Materials, 2020
- DOI for Magnetic and all-optical switching properties of amorphous TbxCo100-x alloys
- Download full text (pdf) of Magnetic and all-optical switching properties of amorphous TbxCo100-x alloys
Contact
- Vassilios Kapaklis
- Gabriella Andersson
- Petra Jönsson
- Visiting address: Ångström Laboratory, Regementsvägen 10, Uppsala, House 4, floor 1 and House 6, floor 1.