论文类型：期刊论文
第一作者：D Wu
通讯作者：G Xu,NL Wang,P Gao
合写作者：L Tong,LY Shi,J Su,GY Zhong,SL Chen,QM Liu
发表刊物：Physical Review Materials
收录刊物：SCI
学科门类：理学
一级学科：物理学
文献类型：J
卷号：3
期号：2
页面范围：24002
ISSN号：2475-9953
发表时间：2019-02-11
影响因子：3.337
摘要：We report a novel quasi-two-dimensional compound of EuTe4 hosting charge density waves (CDW) instability. The compound has a crystallographic structure in a orthorhombic space group Pmmn (No. 59) with cell parameters a=4.6347(2)Å, b=4.5119(2)Å, c=15.6747(10)Å at room temperature. The pristine structure contains consecutive near-square Te sheets separated by corrugated Eu-Te slabs. Upon cooling, the compound experiences a phase transition near 255 K. X-ray crystallographic analysis and transmission electron microscopy measurements reveal strong structural distortions in the low-temperature phase, showing a 1a×3b×2c superstructure with a periodic formation of Te trimers in the monolayer Te sheets, yielding evidence for the formation of CDW order. The charge transport properties show a semiconducting behavior in the CDW state. Density functional theory calculations reveal a Fermi surface nesting-driven instability with a nesting vector in good agreement with the one observed experimentally. Our finding provides a promising system for the study of CDW driven two-dimensional (2D) semiconducting mechanisms, which would shed a light on exploring 2D semiconductors with collective electronic states.
发布期刊链接：https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.3.024002