Selected Applications
attoAFM I
Low Temperature MFM on Artifical Spin Ice
5µm
Frustrated systems are intriguing for physicists since they possess highly degener-
ate ground states with non-zero entropy at 0 K, which can give rise to interesting
new phenomena. A prominent example which has been widely studied in condensed
matter physics is artifical spin ice. Using Magnetic Force Microscopy (MFM), the
group of W. Branford (Imperial College, UK) have studied the magnetic reversal of a
nanostructured permalloy honeycomb lattice, demonstrating the breakdown of the
artifical spin ice regime at low temperatures and in high magnetic fields.
[Data courtesy of W.R. Branford, Imperial College, UK; for more details, see K. Zeissler et al., Scientific Reports 6,
30218 (2016)]
Vortex Barriers in Iron Pnictides
Iron-pnictide high-temperature superconductors are widely studied, but many open
questions still remain. Using an attoAFM I for magnetic force microscopy, the group
of O. Auslaender has studied twin boundaries and their interaction with vortices
over a range of magnetic fields and temperatures. They find that stripes parallel to
the twin boundaries repel vortices, effectively hindering vortex motion, and hence
potentially affecting the critical current in such materials.
[Data courtesy of O. Auslaender (Technion, Israel); for more information, see A. Yagil et al., Phys. Rev. B 94,
064510 (2016)]
MFM for Optimization of Sintered Magnets
MFM image of a NdFeB sintered magnet with the nominal c-axis orientation per-
pendicular to the surface. The sample is in the remanent state but some surface
grains show already magnetization reversal. High resolution imaging allows deeper
insights into the magnetic reversal mechanism and the optimization of magnetic
properties. Image size is 30x30µm².
5µm
(Image courtesy of T. Helbig and O. Gutfleisch, Functional Materials Group, TU Darmstadt, Germany and Fraunhofer
IWKS Hanau, Germany.)
attoMICROSCOPY
Sophisticated Tools for Science
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