Direct observation of the magnetic polaron

Direct Observation of Lattice Polaron Formation in the Local Structure of La1-xCaxMnO3.

S. J. L. Billinge,1 R. G. DiFrancesco,1 G. H. Kwei,2 J. J. Neumeier,3 and J. D. Thompson3 1Department of Physics and Astronomy and Center for Fundamental Materials Research, Michigan State University, East Lansing, Michigan 48824-1116 2Chemistry and Materials Sciences Department, Lawrence Livermore National Laboratory, Livermore, California 94550 3Los Alamos National Laboratory, Los Alamos, New...

Direct observation of stochastic domain-wall depinning in magnetic nanowires.

The stochastic field-driven depinning of a domain wall pinned at a notch in a magnetic nanowire is directly observed using magnetic x-ray microscopy with high lateral resolution down to 15 nm. The depinning-field distribution in Ni80Fe20 nanowires considerably depends on the wire width and the notch depth. The difference in the multiplicity of domain-wall types generated in the vicinity of a no...

Direct observation of resonant tunneling dynamics in high magnetic fields.

Direct Observation of Local Magnetic Field Generated by Micro-Magnet

Using standard nuclear magnetic resonance (NMR) technique and a well-fabricated sample, we have succeeded in directly observing local magnetic field generated by a micro-magnet Ni45Fe55 (the thickness of 400-nm) which was sputtered on an Al layer of 20-nm thickness. Improved sensitivity of our NMR technique enabled us to clearly observe Al-NMR signals, which are confirmed to come from Al nuclei...

Direct observation of magnetic metastability in individual iron nanoparticles.

X-ray photoemission electron microscopy combined with x-ray magnetic circular dichroism is used to study the magnetic properties of individual iron nanoparticles with sizes ranging from 20 down to 8 nm. While the magnetocrystalline anisotropy of bulk iron suggests superparamagnetic behavior in this size range, ferromagnetically blocked particles are also found at all sizes. Spontaneous transiti...