High $T_{c}$: The Discovery of RBCO

It was said by Emerson that ``there is no history; there is only biography.'' This is especially true when the events are recounted by a person who, himself, has been heavily involved and the line between history and autobiography can become blurred. However, it is reasonable to say that discovery itself is not a series of accidents but an inevitable product of each development stage of scientific knowledge as was also pointed out by Holden et al. (1) The discovery of RBCO (2,3) with R = Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu is no exception. In this presentation, I will briefly recount several events that were crucial to the discovery of RBCO: those before 1986 (4) that sowed the seeds in our group important to our later high temperature superconductivity effort; those in 1986 (5) that were critical to our discovery of the 93 K RBCO soon after the discovery of the 35 K high temperature superconductor by M\"{u}ller and Bednorz (6); and those in 1987 when the barrier of the liquid nitrogen boiling temperature of 77 K was finally conquered. \newline \newline 1. G. J. Holton et al., American Scientist 84, 364 (1996). \newline 2. M. K. Wu et al., Phys. Rev. Lett. 58, 908 (1987). \newline 3. P. H. Hor et al., Phys. Rev. Lett. 58, 1891 (1987). \newline 4. C. W. Chu et al., S. S. Comm. 18, 977 (1976); C. W. Chu and V. Diatchenko, Phys. Rev. Lett. 41, 572 (1978); T. H. Lin et al., Phys. Rev. B(RC) 29, 1493 (1984); J. H. Lin et al., J. Low Temp. Phys. 58, 363 (1985). \newline 5. C. W. Chu et al., Phys. Rev. Lett. 58, 405 (1987); C. W. Chu et al., Science 235, 567 (1987). \newline 6. J. G. Bednorz and K. A. M\"{u}ller, Z. Phys. B64, 189 (1986).