The innovation engine for new materials

Exploring the energy landscape of nanoscale magnetic heterostructures

Seminar Group: 


Amanda Petford-Long


Materials Science Division
Argonne National Laboratory


Friday, November 21, 2014 - 4:00pm


ESB 1001


Professor Ram Seshadri

As the dimensions of magnetic materials decrease to the nanoscale, novel distributions of spin can be created. We are exploring the formation of these novel distributions and ways to control them through gaining an understanding of the local energy landscape of the nanostructures. We use a combination of Lorentz TEM and in-situ magnetizing experiments, together with magnetic force microscopy (MFM), to study the micromagnetic behavior at the sub-micron scale in magnetic nanostructures such as heterostructures composed of coupled, patterned magnetic disks, and artificial spin ice arrays. Quantitative analysis of the Lorentz TEM data has been carried out using the transport of intensity equation (TIE) approach, which we have extended to allow us to visualize the magnetic structure in three dimensions. By comparing these data with the results of simulations, we are able to gain a fuller understanding of the various energy terms that contribute to the behavior that we observe.