摘要
We report structural and electronic properties of Na_(2)Ni_(3)S_(4),a quasi-two-dimensional compound composed of alternating layers of[Ni_(3)S_(4)]^(2-)and Na^(+).The compound features a remarkable Ni-based kagome lattice with a square planar configuration of four surrounding S atoms for each Ni atom.Magnetization and electrical measurements reveal a weak paramagnetic insulator with a gap of about 0.5 eV.Our band structure calculation highlights a set of topological flat bands of the kagome lattice derived from the rotated dxz-orbital with C_(3)+T symmetry in the presence of crystal-field splitting.
作者
叶君耀
林益浩
王浩哲
宋志达
冯济
谢韦伟
贾爽
Junyao Ye;Yihao Lin;Haozhe Wang;Zhida Song;Ji Feng;Weiwei Xie;Shuang Jia(International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China;Department of Chemistry,Michigan State University,MI,48824,USA;Hefei National Laboratory,Hefei 230088,China;Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials,Peking University,Beijing 100871,China)
基金
supported by the National Natural Science Foundation of China(Grant Nos.12141002 and 12225401)
the National Key Research and Development Program of China(Grant No.2021YFA1401902)
the CAS Interdisciplinary Innovation Team
the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000)。
