2025/05/01 by Chidiebere I. Nwaogbo, Nwaogbo, Chidiebere I., Chinedu E. Ekuma +1
Materials Science · Physics and Astronomy · #Advanced Thermoelectric Materials and Devices #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2505.00840
openalex publication_date 2025/05/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Two-dimensional (2D) half-metals offer complete spin polarization at the Fermi level, making them candidates for dissipationless spin transport. Yet intrinsic 2D half-metals exhibiting robust topological features, particularly large Chern number anomalous Hall conductivities, remain exceptionally rare. Using first-principles calculations, we identify atomically thin BaNiCl3, a layered halide perovskite (perovskene), as a topological half-metal. It exhibits a high Chern number (C ≥ 2), a large anomalous Hall conductivity of 316~Ω-1,cm-1, and a Fermi velocity of ≈ 0.78 × 106 m/s. The coexistence of complete spin polarization and high carrier velocity suggests low-dissipation spin transport. Spin-orbit coupling opens a sizable topological gap of ∼ 20 meV, yielding nontrivial Berry curvature and enhancing the anomalous Hall response. Ferromagnetism is stabilized by the Ni2+ (d8) configuration and Cl-mediated superexchange, supporting magnetic ordering at elevated temperatures. These results establish BaNiCl3 as a rare intrinsic Chern half-metal, with potential applications in quantum and spintronic technologies.