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摘要: 利用顶角氧掺杂机制,即以二价氧部分替代顶角一价氯,用Ag2O做氧源,在高温高压下制备了单相的Ca3Cu2O4+Cl2-y样品。X射线衍射分析发现,随着Ag2O含量的增加,Ca3Cu2O4+Cl2-y样品的晶格常数a逐渐变小,c逐渐增大,体现了空穴掺杂的本质。进行了电阻率和磁化率测量,没有发现超导性,可能是空穴载流子没有达到合适的浓度所致。
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关键词:
- 高温高压合成 /
- 顶角氧掺杂 /
- Ca3Cu2O4Cl2
Abstract: Using the apical oxygen doping mechanism, i. e. a partial substitution of divalence O for the monovalence Cl, we synthesized Ca3Cu2O4+Cl2-y with Ag2O under high temperature and high pressure. From X-ray diffraction composition analysis, we confirmed that Ca3Cu2O4+Cl2-y crystallizes into a 0212 structure. With increasing the content of Ag2O, we found that lattice parameters a shrinked but c increased. It suggested that it should be hole doping. We also investigated the temperature dependence of the electrical resistivity and DC magnetic susceptibility for two samples, but we didn't observe superconductivity. It maybe resulted from the too low density of hole carrier. -
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