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arXiv · 2405.03212

Using magnetic dynamics to measure the spin gap in a candidate Kitaev material

Xinyi Jiang·Qingzheng Qiu·Cheng Peng·Hoyoung Jang·Wenjie Chen·Xianghong Jin·Li Yue·Byungjune Lee·Sang-Youn Park·Minseok Kim·Hyeong-Do Kim·Xinqiang Cai·Qizhi Li·Tao Dong·Nanlin Wang·Joshua J. Turner·Yuan Li·Yao Wang·Yingying Peng
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Abstract

Materials potentially hosting Kitaev spin-liquid states are considered crucial for realizing topological quantum computing. However, the intricate nature of spin interactions within these materials complicates the precise measurement of low-energy spin excitations indicative of fractionalized excitations. Using Na$_{2}$Co$_2$TeO$_{6}$ as an example, we study these low-energy spin excitations using the time-resolved resonant elastic x-ray scattering (tr-REXS). Our observations unveil remarkably slow spin dynamics at the magnetic peak, whose recovery timescale is several nanoseconds. This timescale aligns with the extrapolated spin gap of $\sim$ 1 $\mu$eV, obtained by density matrix renormalization group (DMRG) simulations in the thermodynamic limit. The consistency demonstrates the efficacy of tr-REXS in discerning low-energy spin gaps inaccessible to conventional spectroscopic techniques.

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Xinyi Jiang, Qingzheng Qiu, Cheng Peng, Hoyoung Jang, Wenjie Chen, Xianghong Jin, Li Yue, Byungjune Lee, Sang-Youn Park, Minseok Kim, Hyeong-Do Kim, Xinqiang Cai, Qizhi Li, Tao Dong, Nanlin Wang, Joshua J. Turner, Yuan Li, Yao Wang, Yingying Peng. 2024-05-06. Using magnetic dynamics to measure the spin gap in a candidate Kitaev material. https://doi.org/10.1038/s41535-025-00737-8

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