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arXiv · 2405.08551

Large diversity of magnetic phases in two-dimensional magnets with spin-orbit coupling and superconductivity

Jannis Neuhaus-Steinmetz·Tim Matthies·Elena Y. Vedmedenko·Thore Posske·Roland Wiesendanger
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Abstract

We classify the magnetic ground states of a 2D lattice of localized magnetic moments which are coupled to a superconducting substrate with Rashba-spin-orbit coupling. We discover a rich magnetic phase diagram with surprisingly complex structures including 2q-spin-spirals, a 2x2-periodic pattern, and skyrmion lattices, self-consistently, using an effective classical spin Hamiltonian and show that the system hosts non-zero 4-spin interactions. Our in-depth analysis of about ten thousand magnetic configurations becomes feasible using contrastive clustering, a recent advanced unsupervised machine learning technique. This work proposes simple few-band systems for non-collinear magnetic states and stimulates further research on topological effects in their self-consistent electronic structure.

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Jannis Neuhaus-Steinmetz, Tim Matthies, Elena Y. Vedmedenko, Thore Posske, Roland Wiesendanger. 2024-05-14. Large diversity of magnetic phases in two-dimensional magnets with spin-orbit coupling and superconductivity. https://arxiv.org/abs/2405.08551

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