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常规导电材料(如金属材料)在温度下降的过程中电阻逐渐减小,这是因为在品格内原子的热“振动”减弱了。当温度下降到绝对零度,热能完全没有了,原子不再晶格内振动了,电阻就消失。所谓物质的超导性,指在绝对零度以上的温度条件下没有任何一点电阻。材料变得具有超导性的这个温度,称为“转变温度”。从1911年发现超导性到1986年,能观察到超导现象的最高温度为20K。后来国际商用机器公司的 Bednorz 和 Maller 研究小组发现 La_(2-x)-Ba_xCuO_4(镧钡铜氧化物)有超过30K 的
The resistance of a conventional conductive material (such as a metal material) decreases gradually as the temperature decreases, because the thermal “vibration” of the atom in the character is weakened. When the temperature dropped to absolute zero, the heat is completely gone, the atoms no longer vibrate within the lattice, and the resistance disappears. The so-called material superconductivity, refers to the temperature above absolute zero without any resistance. The temperature at which the material becomes superconductive is called the “transition temperature.” From the discovery of superconductivity in 1911 to 1986, the maximum temperature at which superconductivity can be observed is 20K. Later, Bednorz and Maller of International Business Machines Corp. found that La_ (2-x) -Ba_xCuO_4 (lanthanum barium copper oxide) had more than 30K