Design of two dimensional materials exhibiting skyrmion

Objective: In this thesis, Gd2B2, GdxSiy, NiI2, and Ni-based Janus NiIBr, NiICl, and NiBrCl two-dimensional materials are investigated to determine their mechanical, electronic, and magnetic properties. Materials and Methods: Calculations of the examined materials were performed within the scope of density functional theory and Monte Carlo simulation methods. Results: Cohesive energy, phonon distribution relations, and molecular dynamics simulations showed that all related two-dimensional materials were stable. It was found that the two-dimensional Gd2B2 has a Curie temperature of 550K and high magnetocrystalline anisotropy energies, and these values can be adjusted by the effect of tensile/compressive strain. It has been found that the magnetic properties of two-dimensional GdxSiy materials vary depending on the number of layers and the stacking type of the gadolinium atom. Starting from the NiI2 crystal, stable Janus monolayer structures of NiIBr, NiICl, and NiBrCl were generated theoretically. Different skyrmion phases were observed in these Janus structures according to the varying magnetic field strength. Conclusion: The magnetic phase transition temperatures of Gd2B2 and GdxSiy are determined and it was theoretically shown that they are suitable materials for spintronic applications. Skyrmion formations were investigated for Ni-based Janus materials and it was revealed that the interaction between magnetic frustration and DM suppressed the formation of skyrmion.