Seminars

Title:Advanced atomistic models of magnetic materials

Abstract: Magneticmaterials maintained huge interests for technological applicationssuch as magnetic recording media (initially on magnetic tapes, now onnm-sized granular media). With the increased necessity to store moreand more data, it is important to constantly improve/renew thecurrent technologies or seek for other magnetic entities (such asdomain walls, skyrmions) to act as a bit of information. Novelresearch fields in magnetism such as spin-electronics (spintronics),opto- and phono-magnetism, neuromorphic and reservoir computingpromise to bring more advanced technologies in our daily life, andthe usage of magnetic nano-particles in bio-medicine to even curesome types of cancer.  The laser-induced manipulation of spinsalso promises to revolutionise the magnetic storage technologies byusing ultrafast processes with low dissipation. 

Inthis work we will explore state-of-the art atomistic models ofmagnetic materials able to simulate billion atoms systems fortechnological applications and fundamental studies. I will start bypresenting the theoretical framework behind atomistic spin dynamics (ASD) which is based on solving the Landau-Lifshitz-Gilbert equationfor various magnetic interactions, implemented in an open-source codecalled VAMPIRE[1,2]. I will also present several applications of theatomistic model for recording media technologies (based on FePt) andnovel 2D magnetic materials, such as CrI₃ [3]and CrCl₃[4].I will then extend the atomistic spin dynamics to an unified model ofspin and molecular dynamics (spin-lattice dynamics -SLD) that takesinto account the lattice degrees of freedom (phonons). Such frameworkcanoffer a deeper understanding of magnon-phonon interactions [5,6],relaxation processes and phonon-driven switching mechanism, which canlead to the development of next-generation magnetic devices.

References

[1]R. F. Evans etal. Journal of Physics: Condensed Matter 26, 103202 (2014)

[2]https://vampire.york.ac.uk

[3]M. Dabrowski et al Nature Communications 13, 5976 (2022)

[4]M.Strungaru et al npj Computational Materials 8, 169 (2022)

[5]Strungaru,Mara, et al. PhysicalReview B 109.22(2024)

[6]Strungaru, Mara, et al. PhysicalReview B 103.2(2021)