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本文简要介绍2个铜氧化物高温超导体(HTSC)系列:CuBa_2Ca_(n-1)Cu_nO_(2n+2+δ),即Cu-12(n-1)n,简称Cu-系;和(Sr,Ca)_(n+1)Cu_nO_(2n)(Cl,O)_2,即“02(n-1)n”-Cl,简称Cl-系。2个系列均含有多层[CuO_2]平面,具有高的超导临界转变温度(T_c)。Cu-1234相的T_c 117K,“0212”-Cl的T_c 80K。特别是Cu-系具有良好的高温高磁场超导性能。Cu-1212与YBa_2Cu_3O_6晶体同构,加之仅含碱土和铜的氧化物,组份经济,操作安全,Cu-系因此具备诱人的应用开发潜力。与常规的HTSC不同,Cl-系的层间构成是卤化物,而非通常的氧化物。根据这一结构特点用“顶角氧”掺杂实现了“0212”-Cl的T_c 80K的超导转变。研究表明“0212-Cl具有与全氧化物HTSC可比的超导性能,预示了对卤氧化物高温超导体群研究和开发的乐观前景。
In this paper, we briefly introduce two series of high temperature superconductors (HTSCs): CuBa_2Ca_ (n-1) Cu_nO_ (2n + 2 + δ) (2n) (Cl, O) _2, that is, “02 (n-1) n” -Cl, Cl- for short. Both series contain multi-layered [CuO 2] planes with high critical critical transition temperature (T_c). T_c 117K for Cu-1234 phase, T_c 80K for “0212” -Cl. In particular, Cu-system has good high temperature and high magnetic field superconductivity. Cu-1212 and YBa 2 Cu 3 O 6 crystals are isomorphic. In addition, alkaline earth oxides and copper oxides alone are economical and safe to operate. Cu-1212 therefore possesses attractive potential for application and development. Unlike conventional HTSCs, the interlayer structure of the Cl-system is a halide rather than the usual oxide. According to this structural feature, the doping of “top corner oxygen” achieved the superconducting transition of T_c 80K of “0212” -Cl. Studies have shown that "0212-Cl has comparable superconducting properties to all-oxide HTSCs and foreshadows optimistic prospects for the research and development of high-temperature superconducting oxyhalides.