How to measure the local Dzyaloshinskii-Moriya Interaction in Skyrmion Thin-Film Multilayers.

The current-driven motion of skyrmions in MnSi and FeGe thinned single crystals could be initiated at current densities of the order of 10 A/m, five orders of magnitude smaller than for magnetic domain walls. The technologically crucial step of replicating these results in thin films has not been successful to-date, but the reasons are not clear. Elucidating them requires analyzing system characteristics at scales of few nm where the key Dzyaloshinskii-Moriya (DM) interactions vary, and doing so in near-application conditions, i.

Halbach Effect at the Nanoscale from Chiral Spin Textures.

Mallinson's idea that some spin textures in planar magnetic structures could produce an enhancement of the magnetic flux on one side of the plane at the expense of the other gave rise to permanent magnet configurations known as Halbach magnet arrays. Applications range from wiggler magnets in particle accelerators and free electron lasers to motors and magnetic levitation trains, but exploiting Halbach arrays in micro- or nanoscale spintronics devices requires solving the problem of fabrication and field metrology below a 100 μm size. In this work, we show that a Halbach configuration of moments can be obtained over areas as small as 1 μm × 1 μm in sputtered thin films with Néel-type domain walls of unique domain wall chirality, and we measure their stray field at a controlled probe-sample distance of 12.

Methyltrimethoxysilane (MTMS)-based silica-iron oxide superhydrophobic nanocomposites.

We report a facile synthesis of superhydrophobic silica-iron oxide nanocomposites via a co-precursor sol-gel process. The choice of the silica precursor (Methyltrimethoxysilane, MTMS) in combination with iron nitrate altered the pore structure dramatically. The influence of iron oxide doping on the structural properties of pristine MTMS aerogel is discussed.

Role of interface coupling inhomogeneity in domain evolution in exchange bias.

Models of exchange-bias in thin films have been able to describe various aspects of this technologically relevant effect. Through appropriate choices of free parameters the modelled hysteresis loops adequately match experiment, and typical domain structures can be simulated. However, the use of these parameters, notably the coupling strength between the systems' ferromagnetic (F) and antiferromagnetic (AF) layers, obscures conclusions about their influence on the magnetization reversal processes.