Computational Study of Microstructure Formation and Magnetic Domain Evolution in FePt Films

Texas A&M Engineering Experiment Station, College Station TX

Investigators

Abstract

TECHNICAL SUMMARY: This award supports computational materials theory and education focused on microstructure evolution in ferromagnetic materials. As promising candidates for ultra-high density magnetic and magneto-optical recording media and for high energy product hard magnets in micro-electromechanical systems, iron-platinum films are attracting extensive experimental research. Microstructure engineering of iron-platinum films faces scientific and technological challenges to further improve their magnetic properties and meet the increasing requirements for high technology applications. The PI aims to establish microstructure property-mechanism relationships and find processing routes to produce the desired microstructures in iron-platinum films. The PI will develop phase field micromagnetic and microelastic models of iron-platinum films in combination with the models of ordering, decomposition, and grain growth to perform simulation studies of crystallographic microstructure formation and ferromagnetic domain evolution. The modeling will treat multiple physical processes during film annealing, including ordering transition, decomposition, grain growth, and simulate the formation of crystallographic microstructures. The magnetic properties of iron-platinum films with the obtained underlying microstructures will be further investigated by modeling and simulation of ferromagnetic domain evolution in the films. The objectives of this project are to (1) develop computational tools for simulating microstructure formation and magnetic domain evolution in iron-platinum films, (2) correlate processing, microstructures, and magnetic properties, (3) provide quantitative explanation of experimental findings, and (4) identify novel microstructures for improved magnetic properties and design appropriate processing to produce such microstructures. The PI also aims to provide insight into the microstructure engineering of other thin film ferromagnetic materials. The supported research and education will train a graduate student in computational materials science, and provide opportunities for undergraduate students to participate and gain experience in simulation-based materials research. Educational modules will be developed for classroom demonstration and hands-on virtual experiments for students. Educational materials will also be developed with an aim to engage high school students and teachers and to foster interest in Simulation-Based Science and Engineering. The PI commits herself to create opportunities for talented women and underrepresented minorities to participate in computational materials research. NON-TECHNICAL SUMMARY: This award supports computational materials theory and education focused on the magnetic properties of thin films. The research will focus on thin films composed of iron and platinum. Recent experiments suggest this material would be a promising candidate for data storage technologies. The PI aims to use computer simulation to model the structure of the material on length scales larger than an atom but much smaller than a thumb. Structure on this scale controls the magnetic properties of the material that make it suitable for recording technology applications. The PI will develop computational tools that will enable her to establish connections between the structure and properties of the material. Once these are understood, the research will focus on addressing how to actually make films with the right structure. The computational tools developed in this research project will advance computational materials science. The research focuses on a technologically important material and how to process it, further contributing to keeping America competitive. The supported research and education will train a graduate student in computational materials science, and provide opportunities for undergraduate students to participate and gain experience in simulation-based materials research. Educational modules will be developed for classroom demonstration and hands-on virtual experiments for students. Educational materials will also be developed with an aim to engage high school students and teachers and to foster interest in Simulation-Based Science and Engineering. The PI commits herself to create opportunities for talented women and underrepresented minorities to participate in computational materials research.