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Bogdan Tanygin

Publications and source records attributed to Bogdan Tanygin.

2 recordsLinked to original sources

Magnetoelectric Properties and Symmetry Classification of Micromagnetic Structures

The magnetoelectric (ME) effects are caused by interactions of the electrical and magnetic subsystems in a solid. Among the applications of ME effects, there are methods of magnetic reversal under the influence of an electrostatic field and the reverse effect. As a result of the theoretical studies carried out in this thesis, we obtained a complete symmetry classification of all the main micromagnetic structures (domain walls, Bloch lines, Bloch points, and magnetic vortices/skyrmions), where the structures were first divided by their magnetic chirality. The organic connection of this classification with the inhomogeneous magnetoelectric effects in them has been shown. The inhomogeneous ME effect is qualitatively described for each symmetry class. Additionally, the known phenomenological theory of these effects is extended to the cases of crystals of cubic, tetragonal, and orthorhombic systems. The obtained results were analyzed for their compatibility with the existing experimental facts, and the possibility of detecting new phenomena has been suggested.

cond-mat.mtrl-sci

Comparison of effective and stable Langevin dynamics integrators

Langevin and Brownian simulations play a prominent role in computational research, and state of the art integration algorithms provide trajectories with different stability ranges and accuracy in reproducing statistical averages. The practical usability of integrators is an important aspect to allow choosing large time steps while ensuring numerical stability and overall computational efficiency. In this work, different use cases and practical features are selected in order to perform a cumulative comparison of integrators with a focus on evaluating the derived velocity and position autocorrelation functions, a comparison that is often disregarded in the literature. A standard industrial open-source software methodology is suggested to compare systematically the different algorithms.

physics.comp-ph