中国物理B ›› 2001, Vol. 10 ›› Issue (4): 335-337.doi: 10.1088/1009-1963/10/4/314

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STRUCTURE AND SUPERCONDUCTIVITY OF Mg(B1-xCx)2 COMPOUNDS

张绍英, 张健, 赵同云, 荣传兵, 沈保根, 成昭华   

  1. State Key Laboratory of Magnetism, Institute of Physics and Center of Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China
  • 收稿日期:2001-02-26 出版日期:2001-04-15 发布日期:2005-07-11
  • 基金资助:
    Project supported by the National Natural Science Foundation of China and the State Key Project of Foundational Research, China.

STRUCTURE AND SUPERCONDUCTIVITY OF Mg(B1-xCx)2 COMPOUNDS

Zhang Shao-ying (张绍英), Zhang Jian (张健), Zhao Tong-yun (赵同云), Rong Chuan-bing (荣传兵), Shen Bao-gen (沈保根), Cheng Zhao-hua (成昭华)   

  1. State Key Laboratory of Magnetism, Institute of Physics and Center of Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China
  • Received:2001-02-26 Online:2001-04-15 Published:2005-07-11
  • Supported by:
    Project supported by the National Natural Science Foundation of China and the State Key Project of Foundational Research, China.

摘要: In this paper, we report on the structural properties and superconductivity of Mg(B1-xCx)2 compounds. Powder X-ray diffraction results indicate that the samples crystallize in a hexagonal AlB2-type structure. Due to the chemical activity of Mg powders, a small amount of MgO impurity phase is detected by X-ray diffraction. The lattice parameters decrease slightly with the increasing carbon content. Magnetization measurements indicate that the non-stoichiometry of MgB2 has no influence on the superconducting transition temperature and the transition temperature width. The addition of carbon results in a decrease of Tc and an increase of the superconducting transition width, implying the loss of superconductivity.

Abstract: In this paper, we report on the structural properties and superconductivity of Mg(B1-xCx)2 compounds. Powder X-ray diffraction results indicate that the samples crystallize in a hexagonal AlB2-type structure. Due to the chemical activity of Mg powders, a small amount of MgO impurity phase is detected by X-ray diffraction. The lattice parameters decrease slightly with the increasing carbon content. Magnetization measurements indicate that the non-stoichiometry of MgB2 has no influence on the superconducting transition temperature and the transition temperature width. The addition of carbon results in a decrease of Tc and an increase of the superconducting transition width, implying the loss of superconductivity.

Key words: superconductivity, magnesium diboride, carbon substitution

中图分类号:  (Metals; alloys and binary compounds)

  • 74.70.Ad
74.62.Dh (Effects of crystal defects, doping and substitution) 74.62.Bf (Effects of material synthesis, crystal structure, and chemical composition) 74.10.+v (Occurrence, potential candidates) 74.25.Ha (Magnetic properties including vortex structures and related phenomena) 74.25.Bt (Thermodynamic properties)