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arXiv · 2305.07734

Disorder-enriched magnetic excitations in the Kitaev quantum spin liquid candidate Na$_2$Co$_2$TeO$_6$

Li Xiang·Ramesh Dhakal·Mykhaylo Ozerov·Yuxuan Jiang·Banasree S. Mou·Andrzej Ozarowski·Qing Huang·Haidong Zhou·Jiyuan Fang·Stephen M. Winter·Zhigang Jiang·Dmitry Smirnov
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Abstract

Using optical magneto-spectroscopy, we investigate the magnetic excitations of Na$_2$Co$_2$TeO$_6$ in a broad magnetic field range ($0\ \rm{T}\leq B\leq 17.5\ \rm{T}$) at low temperature. Our measurements reveal rich spectra of in-plane magnetic excitations with a surprisingly large number of modes, even in the high-field spin-polarized state. Theoretical calculations find that the Na-occupation disorder in \NCTO plays a crucial role in generating these modes. Our work demonstrates the necessity to consider disorder in the spin environment in the search for Kitaev quantum spin liquid states in practicable materials.

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Li Xiang, Ramesh Dhakal, Mykhaylo Ozerov, Yuxuan Jiang, Banasree S. Mou, Andrzej Ozarowski, Qing Huang, Haidong Zhou, Jiyuan Fang, Stephen M. Winter, Zhigang Jiang, Dmitry Smirnov. 2023-05-12. Disorder-enriched magnetic excitations in the Kitaev quantum spin liquid candidate Na$_2$Co$_2$TeO$_6$. https://arxiv.org/abs/2305.07734

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