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 Yb3+ 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.
@article{arxiv.2003.09859,
title = {Mott Transition and Superconductivity in Quantum Spin Liquid Candidate NaYbSe$_2$},
author = {Yating Jia and Chunsheng Gong and Yixuan Liu and Jianfa Zhao and Cheng Dong and Guangyang Dai and Xiaodong Li and Hechang Lei and Runze Yu and Guangming Zhang and Changqing Jin},
journal= {arXiv preprint arXiv:2003.09859},
year = {2020}
}