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arXiv · 2403.11980

Comparative Raman Scattering Study of Crystal Field Excitations in Co-based Quantum Magnets

Banasree S. Mou·Xinshu Zhang·Li Xiang·Yuanyuan Xu·Ruidan Zhong·Robert J. Cava·Haidong Zhou·Zhigang Jiang·Dmitry Smirnov·Natalia Drichko·Stephen M. Winter
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Abstract

Co-based materials have recently been explored due to potential to realise complex bond-dependent anisotropic magnetism. Prominent examples include Na$_2$Co$_2$TeO$_6$, BaCo$_2$(AsO$_4$)$_2$, Na$_2$BaCo(PO$_4$)$_2$, and CoX$_2$ (X = Cl, Br, I). In order to provide insight into the magnetic interactions in these compounds, we make a comparative analysis of their local crystal electric field excitations spectra via Raman scattering measurements. Combining these measurements with theoretical analysis confirms the validity of $j_{\rm eff} = 1/2$ single-ion ground states for all compounds, and provides accurate experimental estimates of the local crystal distortions, which play a prominent role in the magnetic couplings between spin-orbital coupled Co moments.

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Banasree S. Mou, Xinshu Zhang, Li Xiang, Yuanyuan Xu, Ruidan Zhong, Robert J. Cava, Haidong Zhou, Zhigang Jiang, Dmitry Smirnov, Natalia Drichko, Stephen M. Winter. 2024-03-18. Comparative Raman Scattering Study of Crystal Field Excitations in Co-based Quantum Magnets. https://doi.org/10.1103/physrevmaterials.8.084408

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