$d$-Wave Polarization-Spin Locking in Two-Dimensional Altermagnets

Abstract

We report the emergence of an uncharted phenomenon, termed $d$-wave polarization-spin locking (PSL), in two-dimensional (2D) altermagnets. This phenomenon arises from nontrivial Berry connections, resulting in perpendicular electronic polarizations in the spin-up and spin-down channels. Symmetry-protected $d$-wave PSL occurs exclusively in $d$-wave altermagnets with tetragonal layer groups. To identify 2D altermagnets capable of exhibiting this phenomenon, we propose a symmetry-eigenvalue-based criterion, and a rapid method by observing the spin-momentum locking. Using first-principles calculations, monolayer Cr${}_2$X${}_2$O (X = Se, Te) characterizes promising candidates for $d$-wave PSL, driven by the unusual charge order in these monolayers. This unique polarization-spin interplay leads to spin-up and spin-down electrons accumulating at orthogonal edges, enabling potential applications as spin filters or splitters in spintronics. Furthermore, $d$-wave PSL introduces an unexpected spin-driven ferroelectricity in conventional antiferromagnets. Such magnetoelectric coupling positions $d$-wave PSL as an ideal platform for fast antiferromagnetic memory devices. Our findings not only expand the landscape of altermagnets, complementing conventional collinear ferromagnets and antiferromagnets, but also highlight tantalizing functionalities in altermagnetic materials, potentially revolutionizing information technology.

11 Pages, 4 figures

References in corpus (71)

• Berry Phase Effects on Electronic Properties
• Antiferromagnetic spintronics
• Spin current and magneto-electric effect in non-collinear magnets
• Electrical switching of an antiferromagnet
• Altermagnetism: spin-momentum locked phase protected by non-relativistic symmetries
• Crystal Hall effect in Collinear Antiferromagnets
• Symmetry-based Indicators of Band Topology in the 230 Space Groups
• Observation of the Anomalous Hall Effect in a Collinear Antiferromagnet
• Giant momentum-dependent spin splitting in centrosymmetric low Z antiferromagnets
• Efficient Electrical Spin-Splitter Based on Non-Relativistic Collinear Antiferromagnetism
• Electronic structure of quantum materials studied by angle-resolved photoemission spectroscopy
• Relativistic Neel-order fields induced by electrical current in antiferromagnets
• Momentum-Dependent Spin Splitting by Collinear Antiferromagnetic Ordering
• Bulk Topological Invariants in Noninteracting Point Group Symmetric Insulators
• Novel Topological Phase with Zero Berry Curvature
• Multifunctional Antiferromagnetic Materials with Giant Piezomagnetism and Noncollinear Spin Current
• Observation of spin splitting torque in a collinear antiferromagnet RuO2
• Broken Kramers' degeneracy in altermagnetic MnTe
• Giant and tunneling magnetoresistance effects from anisotropic and valley-dependent spin-momentum interactions in antiferromagnets
• Spin current generation in organic antiferromagnets
• Altermagnetism: Exploring New Frontiers in Magnetism and Spintronics
• Tilted spin current generated by the collinear antiferromagnet RuO2
• Direct observation of altermagnetic band splitting in CrSb thin films
• Spontaneous anomalous Hall effect arising from an unconventional compensated magnetic phase in a semiconductor
• Observation of spin-splitter torque in collinear antiferromagnetic RuO${}_2$
• Prediction of unconventional magnetism in doped FeSb2
• Bottom-up design of spin-split and reshaped electronic band structures in spin-orbit-coupling free antiferromagnets: Procedure on the basis of augmented multipoles
• Antidamping torque-induced switching in biaxial antiferromagnetic insulators
• Dual nature of improper ferroelectricity in a magnetoelectric multiferroic
• Observation of Giant Band Splitting in Altermagnetic MnTe
• Quantized Response and Topology of Insulators with Inversion Symmetry
• Crystal Thermal Transport in Altermagnetic RuO2
• Large band-splitting in $g$-wave type altermagnet CrSb
• Fermi liquid instabilities in the spin channel
• Discovery of a metallic room-temperature d-wave altermagnet KV2Se2O
• Higher-order topological insulators protected by inversion and rotoinversion symmetries
• Topological Superconductivity in Two-Dimensional Altermagnetic Metals
• Finite-momentum Cooper pairing in proximitized altermagnets
• Enumeration and representation theory of spin space groups
• Two-dimensional higher-order topology in monolayer graphdiyne
• Nonmagnetic Ground State in RuO${}_2$ Revealed by Muon Spin Rotation
• Three-dimensional mapping of the altermagnetic spin splitting in CrSb
• X-ray Magnetic Circular Dichroism in Altermagnetic $\alpha$-MnTe
• General Theory for the Ferroelectric Polarization Induced by Spin-Spiral Order
• Absence of altermagnetic spin splitting character in rutile oxide RuO${}_2$
• Magnetic octupoles as the order parameter for unconventional antiferromagnetism
• Two-dimensional altermagnets: Superconductivity in a minimal microscopic model
• Chiral-Split Magnon in Altermagnetic MnTe
• Crystal-symmetry-paired spin-valley locking in a layered room-temperature antiferromagnet
• Topological Classification of Crystalline Insulators with Point Group Symmetry
• Spin Space Groups: Full Classification and Applications
• Enumeration of spin-space groups: Towards a complete description of symmetries of magnetic orders
• Perovskite as a spin current generator
• Quantum geometry induced nonlinear transport in altermagnets
• Anomalous Hall effect in $\kappa$-type organic antiferromagnets
• Two-dimensional altermagnets from high throughput computational screening: symmetry requirements, chiral magnons and spin-orbit effects
• Observation of Spin Splitting in Room-Temperature Metallic Antiferromagnet CrSb
• Multipole expansion for magnetic structures: A generation scheme for symmetry-adapted orthonormal basis set in crystallographic point group
• Anisotropy of the anomalous Hall effect in the altermagnet candidate Mn${}_5$Si${}_3$ films
• Description of two-dimensional altermagnetism: Categorization using spin group theory
• Altermagnetic anomalous Hall effect emerging from electronic correlations
• Creation and Manipulation of Higher-Order Topological States by Altermagnets
• Realizing Altermagnetism in Fermi-Hubbard Models with Ultracold Atoms
• Interplay of altermagnetism and weak ferromagnetism in two-dimensional RuF${}_4$
• Anomalous Hall effect in antiferromagnetic perovskites
• Fermi-liquid behavior of non-altermagnetic RuO${}_2$
• Coulomb Drag in Altermagnets
• Notes on altermagnetism and superconductivity
• Fragile Unconventional Magnetism in RuO${}_2$ by Proximity to Landau-Pomeranchuk Instability
• Interface-induced magnetization in altermagnets and antiferromagnets
• Generic Approach to Intrinsic Magnetic Second-order Topological Insulators via Inverted $p-d$ Orbitals

Cited by in corpus (1)

• Spin-Orbit Coupling-Driven Chirality Switching of Spin Waves in Altermagnets