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| Identifier |
000402397 |
| Title |
Structure of magnetic materials with Monte Carlo methods |
| Alternative Title |
Δομή μαγνητικών υλικών με μεθόδους Monte Carlo |
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Author
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Ζερβού, Μιχαέλα- Αρετή
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Thesis advisor
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Χαρμανδάρης, Ευάγγελος
Κομηνέας, Σταύρος
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| Abstract |
Recent observations of chiral structures in magnetic thin films have raised a great interest for the Dzyaloshinskii-Moriya interaction (DMI), as it favors magnetization rotations with a fixed chirality. Thiscouplingoriginatesfromthecombinationoflowstructuralsymmetryandlargespin-orbitcoupling. It has been first proposed in bulk materials lacking space inversion symmetry but it also exists at the interface between a magnetic film and a high spin-orbit coupling adjacent layer. The aim of this thesis concerns the theoretical and computational study of the modification of micromagnetic configurations in magnetic materials, due to the presence of Dzyaloshinskii-Moriya interaction (DMI)and the easy-axis anisotropy that appears at the interface of an ultrathin film. We explore several cases of ultrathin film structures that allow analytical calculations (1D systems,domain walls and spirals), compared with numerical calculations. For the numerical calculations we analyzed a discretized version of a widely used continuum model that describes a magnet Dzyaloshinskii-Moriya interaction (DMI)and the easy-axis anisotropy. Single-flip Metropolis Monte Carlo methods are applied to describe those systems and predict their structural properties. Particularly two series of Monte Carlo simulations are performed. The non-equilibrium case where we use varying temperatures and the equilibrium case where we test the affect of a single fixed temperature on the system. Results are displayed and explained extensively. The algorithms are implemented in Matlab language.
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| Language |
English |
| Issue date |
2016-07-22 |
| Collection
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School/Department--School of Sciences and Engineering--Department of Mathematics and Applied Mathematics--Post-graduate theses
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Type of Work--Post-graduate theses
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| Views |
437 |
Structure of magnetic materials with Monte Carlo methods
