Anomalous Hall Effect in Type IV 2D Collinear Magnets

Abstract

We identify a previously unrecognized class of two-dimensional (2D) collinear magnetic phase that extends beyond the established categories of ferromagnets, antiferromagnets, and altermagnets. These type IV 2D collinear magnets exhibit spin-degenerate bands in the nonrelativistic limit, yet support time-reversal symmetry-breaking responses, such as the anomalous Hall effect (AHE), despite having zero net magnetization. Based on spin layer group analysis, we derive the symmetry criteria for this phase and perform first-principles calculations to screen viable candidate materials from 2D databases. Using monolayer Hf2S as a prototype, we demonstrate that in the absence of spin-orbit coupling, the bands are spin degenerate, while its inclusion induce an AHE driven by spin-polarized and even spin-neutral currents, accompanied by a symmetry-protected, truly full-space persistent spin texture. These findings expand the classification of magnetic phases and broaden avenues for realizing unconventional spintronic functionalities in two dimensions.

6 pages

References in corpus (30)

• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit
• Discovery of intrinsic ferromagnetism in 2D van der Waals crystals
• Anomalous Hall effect
• Antiferromagnetic spintronics
• Two-dimensional materials from high-throughput computational exfoliation of experimentally known compounds
• Wannier90 as a community code: new features and applications
• The Computational 2D Materials Database: High-Throughput Modeling and Discovery of Atomically Thin Crystals
• Altermagnetism: spin-momentum locked phase protected by non-relativistic symmetries
• First Principles Calculation of Anomalous Hall Conductivity in Ferromagnetic bcc Fe
• Crystal Hall effect in Collinear Antiferromagnets
• Observation of the Anomalous Hall Effect in a Collinear Antiferromagnet
• Emergence of the persistent spin helix in semiconductor quantum wells
• Recent Progress of the Computational 2D Materials Database (C2DB)
• Altermagnetism: Exploring New Frontiers in Magnetism and Spintronics
• Orbital ferromagnetism and anomalous Hall effect in antiferromagnets on distorted fcc lattice
• Observation of plaid-like spin splitting in a noncoplanar antiferromagnet
• Crystal Thermal Transport in Altermagnetic RuO2
• Direct mapping of the formation of a persistent spin helix: Supplementary information
• Persistent spin texture enforced by symmetry
• Twisted Magnetic Van der Waals Bilayers: An Ideal Platform for Altermagnetism
• Topological magneto-optical effects and their quantization in noncoplanar antiferromagnets
• Catalog of Unconventional Magnons in Collinear Magnets
• Description of two-dimensional altermagnetism: Categorization using spin group theory
• Bilayer stacking A-type altermagnet: A general approach to generating two-dimensional altermagnetism
• Emergent properties of van der Waals bilayers revealed by computational stacking
• The role of spin-flip transitions in the anomalous Hall effect of FePt alloy
• Emerging Two-Dimensional Magnetism in Nonmagnetic Electrides Hf2X (X = S, Se, Te)
• Encyclopedia of emergent particles in 528 magnetic layer groups and 394 magnetic rod groups
• Full-zone Persistent Spin Textures with Giant Spin Splitting in Two-dimensional Group IV-V Compounds
• Magnetic surface on nonmagnetic bulk of electride Hf2S

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