These micromagnetic simulations are done in MATLAB. Each rotating vector represents an individual nanoparticle under the macrospin approximation. These simulations attempt to see if treating individual particles as spins in a typical micromagnetic discretization scheme yields realistic results. Time-domain measurement of these type of dynamics was the focus of my dissertation work at the University of South Carolina. This computational model is an extension of a previous work of Ru Zhu. It extends the former by adapting it to CPUs (rather than GPUs), going to a 3-D model space, animating the simulation, and various other changes including plotted outputs not shown in the video.
Link to my paper on inductive time-domain measurements of magnetization dynamics of dense collections of magnetic nanoparticles.
Link to my dissertation on inductive time-domain measurements of magnetization dynamics in ferrofluids.
Simulations looking at chains of macro spins responding only to applied fields and dipole-dipole interactions.
Slideshow of my research on inductive time-domain measurements of magnetization dynamics of dense collections of magnetic nanoparticles.
Until 2021 I was a researcher in ferrofluid dynamics at the University of South Carolina's Nanocenter. Below is some of my past work as a graduate student in this area.
Nanoparticle Chain Simulations
MATLAB Micromagnetics
Download the MATLAB Micromagnetic Animation Code Here:
Master's Thesis -----------------------------------------------------------------------
In this micromagnetic simulation each vector represents the average of all local atomic magnetic moments over the surrounding volume. Here a cubic magnetic nanoparticle is modeled under a dynamical external field to see how the internal magnetization vectors change directions. As the cube gets larger the exchange effect, being a short-range interaction, falls off and the dipolar field becomes dominant. This leads to the moments to begin to diverge and leads to complex buckling of the coherent magnetization structure. Spin waves are set up as the exchange interaction takes longer to transmit across the volume, leading to phase differences.
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Nano-Magnetic Research
Doctoral Dissertation------------------------------------------------------
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