When it comes to layered quantum materials, current understanding only scratches the surface; so demonstrates a new study from the Paul Scherrer Institute PSI. Using advanced X-ray spectroscopy at the Swiss Light Source SLS, researchers uncovered magnetic phenomena driven by unexpected interactions between the layers of a kagome ferromagnet made from iron and tin. This discovery challenges assumptions about layered alloys of common metals, providing a starting point for developing new magnetoelectric devices and rare-earth-free motors.
Patterns are everything. With quantum materials, it’s not just what they’re made of but how their atoms or molecules are organised that gives rise to the exotic properties that excite researchers with their promise for future technologies.
Graphene showed this to the world: arranged into single layers of a hexagonal lattice, common-or-garden carbon atoms could exhibit extraordinary electronic properties. Research over the last decade has since been dedicated to discovering whether other two-dimensional arrays of atoms, either alone or stacked into a three-dimensional material, can reveal similarly novel behaviours.
The kagome lattice, which takes its name from a type of Japanese basket woven in corner sharing triangles, is another two-dimensional pattern that has excited researchers with its ability to host exotic quantum states, ranging from superconductivity to unconventional magnetism.
Yet until now, research has focused on electronic and magnetic properties in two-dimensions of the material. The latest results in Fe3Sn2 – a ferromagnetic material made of iron and tin atoms arranged into the intricate kagome pattern – change that.
Read more on the PSI website
Image: The kagome ferromagnet, Fe3Sn2 hosts spin waves – magnetic ripples arising from collective excitations of electron spins (shown here as golden arrows). The new findings reveal that the spin-waves are influenced by unexpected interactions between the layers in the material.
Credit: ©Wenliang Zhang / Paul Scherrer Institute PSI