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arXiv · 2408.15754

Emergent scalar-chirality \& colossal transverse-magnetoresponse in strongly correlated nodal-line half-metal

Jyotirmoy Sau·Sourav Chakraborty·Sourabh Saha·Kalpataru Pradhan·Anamitra Mukherjee·Manoranjan Kumar
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Abstract

Understanding the interplay of strong correlation and temperature in nodal-line semimetals can offer novel ways to control spin currents. Here we consider the 3d-5d double-perovskite Ba$_{2}$CoWO$_{6}$, which features mirror-symmetry-protected nodal-lines, strong Co-site interactions, and spin-orbit coupling (SOC) at W sites. Our first principles and exact diagonalization results reveal a half-metallic ground state with high-spin Co and topologically non-trivial bands. We demonstrate that SOC gaps out nodal points, causes band-inversion and generates anomalous Hall response. A semi-classical Monte Carlo finite-temperature simulation of five-orbital Hubbard model uncovers an emergent Co-spin scalar chirality and colossal positive transverse-magnetoresponse. We predict the temperature and magnetic field scales for the tunability of scalar-chirality and magnetoresponse.

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Jyotirmoy Sau, Sourav Chakraborty, Sourabh Saha, Kalpataru Pradhan, Anamitra Mukherjee, Manoranjan Kumar. 2024-08-28. Emergent scalar-chirality \& colossal transverse-magnetoresponse in strongly correlated nodal-line half-metal. https://arxiv.org/abs/2408.15754

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