Speaker
Description
Altermagnets are a recently identified class of magnetic materials that, like antiferromagnets, exhibit zero net magnetization but display spin-split electronic bands in certain regions of the Brillouin zone [1]. Unlike conventional antiferromagnets, altermagnets can support spin-polarized currents, making them a unique hybrid between antiferromagnets and ferromagnets. This duality provides several advantages for spintronic applications, including spin currents without stray fields, robustness against external magnetic fields, ultrafast spin dynamics, and symmetry-driven spin phenomena.
Two-dimensional ($2$D) altermagnetic materials are particularly compelling. Not only were they initially predicted theoretically, but in the presence of spin-orbit coupling (SOC), some exhibit weak ferromagnetism due to non-trivial spin-momentum locking that cants their magnetic moments [2].
In this poster, we present a combined density functional theory and symmetry analysis of the electronic structure of $2$D transition metal tetrafluorides. We examine how the net magnetic moment scales with SOC strength and use group theory to derive an effective spin Hamiltonian that captures both the spin splitting and spin-momentum locking of the bands. By disentangling altermagnetic contributions from those induced by SOC, we clarify the role of spin-orbit interaction in modifying the intrinsic altermagnetic behavior. Our results highlight the emergence of weak ferromagnetism and non-trivial spin textures in $2$D altermagnets, pointing toward new directions in the design of next-generation spintronic materials.
Acknowledgements
This work was supported by the Slovak Research and Development Agency under the Contract no. SK-SRB-23-0033, and by the Ministry of Education, Research, Development and Youth of the Slovak Republic provided under Grant No. VEGA 1/0104/25.
References
[1] L. Šmejkal et al., “Emerging Research Landscape of Altermagnetism,” Physical Review X, vol. 12, no. 4. American Physical Society (APS), Dec. 08, 2022. https://doi.org/10.1103/physrevx.12.040501
[2] M. Milivojević et al., “Interplay of altermagnetism and weak ferromagnetism in two-dimensional RuF4,” 2D Materials, vol. 11, no. 3. IOP Publishing, p. 035025, May 30, 2024. https://doi.org/10.1088/2053-1583/ad4c73
