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arXiv · 2012.00940

Field-induced quantum spin disordered state in spin-1/2 honeycomb magnet Na2Co2TeO6

Abstract

Spin-orbit coupled honeycomb magnets with the Kitaev interaction have received a lot of attention due to their potential of hosting exotic quantum states including quantum spin liquids. Thus far, the most studied Kitaev systems are 4d/5d-based honeycomb magnets. Recent theoretical studies predicted that 3d-based honeycomb magnets, including Na2Co2TeO6 (NCTO), could also be a potential Kitaev system. Here, we have used a combination of heat capacity, magnetization, electron spin resonance measurements alongside inelastic neutron scattering (INS) to study NCTO's quantum magnetism, and we have found a field-induced spin disordered state in an applied magnetic field range of 7.5 T < B (vertical to b-axis) < 10.5 T. The INS spectra were also simulated to tentatively extract the exchange interactions. As a 3d-magnet with a field-induced disordered state on an effective spin-1/2 honeycomb lattice, NCTO expands the Kitaev model to 3d compounds, promoting further interests on the spin-orbital effect in quantum magnets.

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Gaoting Lin, Jaehong Jeong, Chaebin Kim, Yao Wang, Qing Huang, Takatsugu Masuda, Shinichiro Asai, Shinichi Itoh, Gerrit Günther, Margarita Russina, Zhilun Lu, Jieming Sheng, Le Wang, Jiucai Wang, Guohua Wang, Qingyong Ren, Chuanying Xi, Wei Tong, Langsheng Ling, Zhengxin Liu, Liusuo Wu, Jiawei Mei, Zhe Qu, Haidong Zhou, Xiaoqun Wang, Je-Geun Park, Yuan Wan, Jie Ma. 2020-12-02. Field-induced quantum spin disordered state in spin-1/2 honeycomb magnet Na2Co2TeO6. https://doi.org/10.1038/s41467-021-25567-7

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