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arXiv · 2003.09859

Mott Transition and Superconductivity in Quantum Spin Liquid Candidate NaYbSe$_2$

Yating Jia·Chunsheng Gong·Yixuan Liu·Jianfa Zhao·Cheng Dong·Guangyang Dai·Xiaodong Li·Hechang Lei·Runze Yu·Guangming Zhang·Changqing Jin
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Abstract

The Mott transition is one of the fundamental issues in condensed matter physics, especially in the system with antiferromagnetic long-range order. However the Mott transition in quantum spin liquid (QSL) systems without long-range order is rare. Here we report the observation of the pressure-induced insulator to metal transition followed by the emergence of superconductivity in the QSL candidate NaYbSe2 with triangular lattice of 4f Yb$_3^+$ ions. Detail analysis of transport properties at metallic state shows an evolution from non-Fermi liquid to Fermi liquid behavior when approaching the vicinity of superconductivity. An irreversible structure phase transition occurs around 11 GPa is revealed by the X-ray diffraction. These results shed light on the Mott transition and superconductivity in the QSL systems.

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Yating Jia, Chunsheng Gong, Yixuan Liu, Jianfa Zhao, Cheng Dong, Guangyang Dai, Xiaodong Li, Hechang Lei, Runze Yu, Guangming Zhang, Changqing Jin. 2020-03-22. Mott Transition and Superconductivity in Quantum Spin Liquid Candidate NaYbSe$_2$. https://doi.org/10.1088/0256-307x/37/9/097404

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