Girl Scout Troops@BNL

Update 2012-10-18: You can now read the official BNL press release:
http://www.bnl.gov/newsroom/news.php?a=23393

It was great to see all of you and your interest in science. I enjoyed contributing to the lesson. Here is possibly the smallest Girl Scout logo every made :) The total width of the logo is ~7.5 micrometers. That's the same size of a red blood cell!! The thickness of the logo was only ~30 nanometers. Click here to download the logo in other colors. Good luck with your future science interactions and feel free to ask questions by clicking on comments below. 

--Javier

The image to the left is of the Girl Scouts logo captured using Atomic Force Microscopy. The troop  had a hands on nano lesson explaining the fundamentals of Scanning Probe Microscopy before they saw the equipment in action at the CFN. The logo was fabricated using a top-down electron beam lithography process. The raised areas are 30nm of Cobalt on top of Silicon.

NSF Review Panelist

I would like to thank Program Director Dr. Juan Figuero for the opportunity to serve as a technical reviewer panelist at the National Science Foundation.

APS March Meeting 2012 Talk

I will be presenting our work entitled:

 High Frequency Excitation of Nanometer-Scale, Strongly Coupled FM / NM / FM Disks 

Abstract:
There is great interest in the manipulation of magnetic domains in nanostructures from both a fundamental and applications perspective. In particular, the use of resonant frequency excitations permits a power reduction of the driving forces necessary to induce detectable motion in magnetic vortex structures. Here we present an experimental and numerical study of patterned tri-layered disk stacks which are composed of 25nm Permalloy | 1nm Copper | 15nm Permalloy, excited at resonance, ranging from 250-500nm in radii. In-situ Lorentz microscopy was used to acquire time averaged real space images of the vortices' gyrotropic motion and micromagnetic simulations were implemented to further understand the coupled dynamics between the ferromagnetic layers across the thin non-magnetic spacer layer. We discuss the effects of interlayer coupling on the vortex trajectories and resonant frequencies for the individual ferromagnetic layers.

The figure above shows the gyrotropic motion of a vortex core under a high frequency applied magnetic field.