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arXiv · 2506.13696

Photomagnetic-Chiral Anisotropy mediated by Chirality-Driven Asymmetric Spin Splitting

Tianwei Ouyang·Hang Su·Wanning Zhang·Yingying Duan·Yuxi Fang·Shunai Che·Yizhou Liu
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Abstract

Photo-magnetic effects (PMEs), intrinsic to transition metals, arises from the interaction between light-induced angu-lar momentum and electronic spin. These effects are suppressed in noble metals with high symmetry and electron density. Introducing chiral structures can induce photomagnetic-chiral anisotropy (PM-ChA) of metals by linking chirality and spin dynamics. However, a theoretical explain remains elusive. Here, we investigated the mechanism of PM-ChA in tetrahelix-stacked chiral nanostructured gold chains (CNACs) using first-principles calculations. Non-equilibrium Green's function calculations reveal that chiral potentials enhance spin channel asymmetry by amplify-ing spin-orbit coupling (SOC)-induced spin splitting. Real-time time-dependent density functional theory simulations further identify SOC as the bridge connecting chiral spintronics to PME, where chirality-driven spin flips from asymmetric geometries generate opposing photomagnetic fields in materials of different handedness. These findings are consistent with experimental observations in chiral nanostructured gold films and provide a theoretical instruction for design metallic spintronic devices.

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Tianwei Ouyang, Hang Su, Wanning Zhang, Yingying Duan, Yuxi Fang, Shunai Che, Yizhou Liu. 2025-06-16. Photomagnetic-Chiral Anisotropy mediated by Chirality-Driven Asymmetric Spin Splitting. https://doi.org/10.1103/llys-8b4p

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