= 아 래 =
1. 일 시 : 2014. 11. 14 (금), 16:00 ~
2. 장 소 : 신소재 공학과 2427호
3. 연 사 : Dr. Amanda K. Petford-Long (Argonne National Laboratory)
4. 제 목 : Understanding the behavior of nanoscale magnetic heterostructures: how microscopy can help
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 have used 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 of 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 also 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.