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四个月前,“高温超导体”仅指含稀土的氧化铜。经过近几个月的努力,已很有可能制备无稀土、甚至无铜的超导体。在这之前,研究人员大多致力于所谓的1-2-3化合物(YBa_2Cu_3O_7)以及以稀土元素铕(Eu)和钆(Gd)取代钇(Y)的同系物。但现在热衷于含铊(Tl)或铋(Bi)的氧化铜和无铜氧化铋,因它们具有令人感兴趣的结构和特性。人们最感兴趣的特性是材料变成超导体的转化温度Tc。在Tc温度下,材料的电阻为零。直至今年,人们确认1-2-3化合物的
Four months ago, “high temperature superconductor” only refers to rare earth-containing copper oxide. After several months of hard work, it has become possible to prepare rare earth-free or copper-free superconductors. Until now, researchers mostly focused on so-called 1-2-3 compounds (YBa_2Cu_3O_7) and homologues replacing yttrium (Y) with rare earth elements such as europium (Eu) and gadolinium (Gd). But now they are interested in copper oxide and copper-free bismuth oxide containing thallium (Tl) or bismuth (Bi) due to their interesting structure and properties. One of the most interesting characteristics of people is the transformation temperature Tc of the material into a superconductor. At Tc temperature, the resistance of the material is zero. Until this year, people have confirmed 1-2-3 compounds