摘要
We report the synthesis,structural and physical properties of a new layered transition metal arsenide Na4Cu3TaAs4.This material adopts the space groupⅠ√2 m,with lattice parameters of a=5.9101(3)?and c=13.8867(12)?.This structure contains two layers of Na sandwiched by antiPb O-type(Cu/Ta)As layers,similar to the"111"-type ironbased superconductor Na Fe As.The transition metal sites are occupied by 75%Cu and 25%Ta,with Ta forming a well-defined superstructure.Cu and Ta were determined to be+1 and+5 oxidation state respectively.The band structure of the Na4Cu3TaAs4 measured by angle resolved photoemission spectroscopy(ARPES)is in good agreement with the density functional theory(DFT)calculation.Both ARPES and resistivity measurement indicate that this material exhibits metallic behavior with p-type carriers.Magnetic susceptibility measurement shows that the material exhibits nearly T-independent diamagnetism.This new material extends the material system with anti-Pb O-type layers and offers a good playground to investigate this material system further.
我们报道了一种新的过渡金属层状砷化物Na4Cu3TaAs4的合成、结构和物理性质.这种材料采用Ⅰ√2 m空间群,晶胞参数为a=5.9101(3)?,c=13.8867(12)?.这个材料的结构中包含两层Na,而Na夹在反氧化铅型(Cu/Ta)As层之间,类似于"111"型铁基超导体NaFeAs.过渡金属位由75%的Cu和25%的Ta占据,Ta形成了明确的√2超结构.Cu和Ta分别为+1和+5价.角分辨光电子能谱测得的Na4Cu3TaAs4能带结构能够和DFT计算结果良好地吻合.角分辨光电子能谱和输运测量均表明该材料表现为金属行为,具有p型载流子.磁化率测量表明该材料表现为几乎不依赖温度的抗磁性.这种新材料扩展了含有反氧化铅型层的材料系统,并为进一步研究该材料系统提供了一个很好的平台.
作者
Fanbao Meng
Mengzhu Shi
Shengtao Cui
Kunling Peng
Naizhou Wang
Zhe Sun
Jianjun Ying
Xianhui Chen
孟凡保;石梦竹;崔胜涛;彭坤岭;王乃舟;孙喆;应剑俊;陈仙辉(Key Laboratory of Strongly Coupled Quantum Matter Physics,Chinese Academy of Sciences,Hefei National Laboratory for Physical Sciences at Microscale,Department of Physics,University of Science and Technology of China,Hefei 230026,China;National Synchrotron Radiation Laboratory,University of Science and Technology of China,Hefei 230026,China;Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China;CAS Center for Excellence in Superconducting Electronics(CENSE),Shanghai 200050,China;CAS Center for Excellence in Quantum Information and Quantum Physics,Hefei 230026,China)
基金
supported by the National Natural Science Foundation of China(11888101 and 11534010)
Anhui Initiative in Quantum Information Technologies(AHY160000)
the Strategic Priority Research Program of Chinese Academy of Sciences(XDB25000000)
the National Key Research and Development Program of the Ministry of Science and Technology of China(2016YFA0300201 and 2017YFA0303001)
the Key Research Program of Frontier Sciences,CAS,China(QYZDYSSW-SLH021).
