1. A ‘Writable’ Next-generation Magnetic Media Material Gregory B. Thompson, University of Alabama Tuscaloosa, DMR 0547445 Intellectual Merit Ta enrichment at a triple junction grain boundary Research motivation: Hard drive storage capacity has been increasing at an exponential rate. To continue this trend, a new class of thermally stable, hard-magnets will be required. However, harder magnetic materials can be too strong to switch using conventional write heads in your computer. Exchange-coupled composites (ECC) and graded magnetocrystalline anisotropy K u thin films have been proposed to solve this problem by allowing a lower required write field for a given thermal stability. Though several simulations have been reported to yield these advantageous properties, with some experimental verification with EEC designs, there are relatively fewer experimental reports on the fabrication and measurements for gradient soft-to-hard magnetic materials. In the present work, the K u has been varied by changing the composition in a [Fe x Ni 1-x ] 50 Pt 50 film. Results: The Energy Dispersive Spectroscopy chemical line profile confirmed the compositional gradient between Ni and Fe, fig. (a). Homogenization of the gradient did not occur during the in situ annealing during growth to promote chemical ordering and [001] epitaxy. The film was then electron beam lithographically patterned into isolated nano-dots of ~ 70 nm, fig. (b). Post patterning, the film retained good magnetocrystalline (easy-axis) alignment and increased coercivity. Fig. (c). Unfortunately, the e-beam patterning size was insufficient in yielding dots where coherent reversal could be achieved. Hence, the writing field-to- thermal stability absolute value was very low. By normalizing the graded K u results to a single composition Fe 23 Ni 25 Pt 52 film, ≈ 41% relative improvement was shown, indicating that such gains are possible. (a) (b) (c) STEM-HAADF cross-section image of the graded [Fe x Ni 1-x ] 50 Pt 50 film Chemical line profile showing the gradation between Ni and Fe. E-beam lithographically patterned array of magnetic nano-dots. Hysteresis of patterned, magnetic nano-dots

2. Education and Dissemination of Atom Probe Tomography Research Gregory B. Thompson, University of Alabama Tuscaloosa, DMR 0547445 Broader Impact Atom probe tomography (APT) is a characterization technique that provides unprecedented, three-dimensional reconstruction of atoms, with equal detection sensitivity for every atom, in a material. This technique has been extensively used throughout this NSF research grant. Dr. Karen (Torres) Henry, a Hispanic American female doctoral student that was supported by this grant, received a National Research Council Post Doctoral Fellowship to conduct APT research at the National Institute for Standards and Technology (NIST). Most recently, she has take full time employment at Intel to carry on research and development in semiconductors using APT. This grant has supported our national technical workforce development needs. Professor Thompson continues to contribute to the educational efforts for atom probe tomography. He was an invited instructor at the Idaho National Laboratory’s Center for Advanced Energy Studies “Atom Probe Tomography” Workshop held August 3 – 5, 2011. Professor Thompson lectured on data visualization, data analysis methods, reconstructions, and assisted in hands-on demos. Professor Thompson was the Chair organizer for the 53 rd International Field Emission Symposium (IFES) held May 20 th -25 th on the campus of the University of Alabama. This is the première meeting for the atom probe and high field nanoscience communities. The meeting had nearly 180 registered participants, with 42 being students. Over 15 countries were represented in the meeting. The symposium had a pre-meeting workshop with three separate lectures; over 110 technical talks given as plenary, invited and contributed presentations; and 72 posters discussed during two evening sessions. The excursion of the conference was to the NASA Space and Rocket Center in Huntsville, AL, making a memorable and technically enriching experience for all those that participated. Please visit www.ifes2012.ua.edu for more information. APT workshop attendees at the Idaho National Laboratory Attendees of IFES 2012, held on the campus of The University of Alabama