摘要
We investigate the structural variation and physical properties of layered La_(2)M_5As_(3)O_(2)(M=Cu,Ni)compound upon Co doping.It is found that the substitution of Co ion just induces the monotonous change of lattice constants without observing the anomalous kink in superconducting La_(2)(Cu_(1-x)Nix)_(5)As_(3)O_(2)solid-solutions.Meanwhile,this doping barely changes As–As bond length in[M_(5)As_(3)]^(2-)subunit(±2%),being significantly smaller than 7%shrinkage of that in La_(2)(Cu_(1-x)Nix)_(5)As_(3)O_(2).Therefore,the doping dependence of crystal structure exhibits similar trend with Ba_(1-x)K_xFe_(2)As_(2)without the interference of As1–As 2 bonding,implying that the Co substitution for Cu/Ni is hole-doped.In terms of physical property,La_(2)(Cu1-xCox)~5As_(3)O_(2)turns into itinerant ferromagnetic metal,while La_(2)(Ni_(1-x)Co_(x))_(5)As_(3)O_(2)shows paramagnetism and suppressed structural phase transition upon Co-doping.The distinct structural variation and absence of superconductivity provide important clues to understand the effect of As–As bond in[M_(5)As_(3)]^(2-)subunit.
作者
Lei Yang
Yan-Peng Song
Jun-Jie Wang
Xu Chen
Hui-Jing Du
Jian-Gang Guo
杨蕾;宋艳鹏;王俊杰;陈旭;杜会静;郭建刚(Key Laboratory for Microstructural Material Physics of Hebei Province,School of Science,Yanshan University,Qinhuangdao 066004,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Songshan Lake Materials Laboratory,Dongguan 523808,China)
基金
Projected supported by the National Natural Science Foundation of China(Grant Nos.51922105 and 51772322)
the National Key Research and Development Program of China(Grant Nos.2017YFA0304700 and 2016YFA0300600)
the Beijing Natural Science Foundation,China(Grant No.Z200005)。
