Spin Chern number in altermagnets

Abstract

This work explores the topological properties of altermagnets, a novel class of collinear magnetic materials. We employ equivariant K-theory of magnetic groups and Hamiltonian models to formulate a robust $C_4^z\mathbb{T}$ topological invariant to classify 2D and 3D altermagnetic systems. Our findings demonstrate that the spin Chern number serves as a robust topological index, corresponding to the half-quantized Chern number of the divided Brillouin zone. This indicator enables the prediction of a topologically protected 2D altermagnetic insulators and 3D Weyl altermagnetic semimetals, highlighting the relationship between altermagnetism and topological phases. Furthermore, our results provide a pathway to the exploration of topological applications in $d$-wave altermagnetic materials.

12 pages, 5 figures

References in corpus (34)

• Topological Insulators
• Topological insulators and superconductors
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Berry Phase Effects on Electronic Properties
• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Topological Insulators in Three Dimensions
• Classification of topological quantum matter with symmetries
• WannierTools: An open-source software package for novel topological materials
• Altermagnetism: spin-momentum locked phase protected by non-relativistic symmetries
• Crystal Hall effect in Collinear Antiferromagnets
• Time Reversal Polarization and a Z_2 Adiabatic Spin Pump
• Observation of the Anomalous Hall Effect in a Collinear Antiferromagnet
• Efficient Electrical Spin-Splitter Based on Non-Relativistic Collinear Antiferromagnetism
• Momentum-Dependent Spin Splitting by Collinear Antiferromagnetic Ordering
• Giant and tunneling magnetoresistance effects from anisotropic and valley-dependent spin-momentum interactions in antiferromagnets
• Altermagnetism: Exploring New Frontiers in Magnetism and Spintronics
• Spontaneous anomalous Hall effect arising from an unconventional compensated magnetic phase in a semiconductor
• Prediction of unconventional magnetism in doped FeSb2
• Robustness of the Spin-Chern number
• Antiferromagnetism in RuO${}_2$ as $d$-wave Pomeranchuk instability
• Bottom-up design of spin-split and reshaped electronic band structures in spin-orbit-coupling free antiferromagnets: Procedure on the basis of augmented multipoles
• Observation of plaid-like spin splitting in a noncoplanar antiferromagnet
• Crystal Thermal Transport in Altermagnetic RuO2
• Twisted equivariant matter
• Topological Superconductivity in Two-Dimensional Altermagnetic Metals
• Landau Theory of Altermagnetism
• Topological transition from nodal to nodeless Zeeman splitting in altermagnets
• Phase diagrams of disordered Weyl semimetals
• Altermagnetism and magnetic groups with pseudoscalar electron spin
• Intrinsic anomalous Hall effect in altermagnets
• Spin-Resolved Topology and Partial Axion Angles in Three-Dimensional Insulators
• Quasi-one-dimensional spin transport in altermagnetic $Z^3$ nodal net metals
• Projected spin texture as a bulk indicator of fragile topology
• Spin Weyl Topological Insulators

Cited by in corpus (7)

• Model Hamiltonian for Altermagnetic Topological Insulators
• The emergence of net chirality in two-dimensional Dirac fermions system with altermagnetic mass
• Spin-biased quantum spin Hall effect in altermagnetic Lieb lattice
• Quantum anomalous Hall conductivity in altermagnets under applied magnetic field
• Interface controlled Berry phase and anisotropic spin-charge conversion in altermagnet-topological insulator bilayers
• Altermagnetism Induced Bogoliubov Fermi Surfaces Form Topological Superconductivity
• Coexistence of d-Wave Altermagnetism and Topological States in Janus FeSeX (X = S, Te) Monolayers