Interlayer Interaction as a Mechanism for Engineering Topological Textures in Thin Films: From Meron Crystals to Induced Skyrmions

Session Information

Location: amf. P7 | "Gheorghe Asachi" Technical University of Iași (TUIAȘI)
Day: 4. Thursday 18
Time: 15:10-15:30
Chairperson: Ionel Dumitrel Ghiba

Presentation Details

Presentation Type: Oral presentation
Title: Interlayer Interaction as a Mechanism for Engineering Topological Textures in Thin Films: From Meron Crystals to Induced Skyrmions
Abstract: Topological magnetic textures, including skyrmions and merons, are promising for next-generation spintronic applications due to their nanoscale dimensions, stability, and efficient current-driven dynamics. Although research has primarily focused on monolayer systems, synthetic antiferromagnetic (SAF) bilayers introduce an additional degree of freedom through interlayer exchange coupling (J).

Large-scale Monte Carlo simulations based on a discrete Heisenberg model, incorporating exchange, Dzyaloshinskii-Moriya interaction (DMI), and triaxial anisotropy, are used to systematically explore the magnetic texture space of SAF bilayers. The results demonstrate that interlayer interactions are a critical factor in stabilizing complex magnetic textures that remain unstable in isolated monolayers.

Three distinct regimes are identified, governed by the competition between the external magnetic field (H) and interlayer exchange coupling (J):

1. Topological Phase Transformation: At intermediate magnetic fields, a transition occurs in which monolayer skyrmion lattices are reconstructed into robust meron-antimeron crystals, driven by the energy minimization of vertical flux-closing patterns.

2-Interlayer-Induced Topology: In high-field regimes where the monolayer is purely field-polarized, the introduction of SAF coupling triggers the nucleation of stable skyrmion lattices by effectively screening the Zeeman energy.

3. Anisotropy-Mediated Stability: The energetic penalty associated with core polarization is analyzed, demonstrating how easy-plane anisotropy dictates the transition between meron and skyrmion characteristics.

Mapping phase stability through detailed energy decomposition and topological charge (Q) analysis provides a theoretical framework for designing layered magnetic heterostructures with tailored topological properties. These findings offer new insights into the control of magnetic textures in multicomponent thin films.

Presenter

Prof Ümit Akıncı
Dokuz Eylül University | Türkiye

Authors

1. Akıncı, Ümit | Department of Physics, Dokuz Eylül University, TR-35160 Izmir, Turkey
2. Doğan, Gülşen | The Graduate School of Natural and Applied Sciences, Dokuz Eylül University, Tr-35160 İzmir, Turkey