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J. Georg Bednorz and K. Alex Müller, working at IBM’s Zurich research laboratory, tested that assumption anyway, systematically substituting elements into a family of copper-oxide perovskites. In a barium-doped lanthanum copper oxide compound, they found a sharp drop in resistivity beginning near 35 kelvin — still cold by ordinary standards, but 12 kelvin above the prior record, in a material class nobody expected to superconduct at all. They published cautiously, titling the paper “Possible High- $T_c$ Superconductivity in the Ba-La-Cu-O System” in Zeitschrift für Physik B in April 1986 [ 4 ] . The paper drew no citations for the rest of that year. Once other laboratories reproduced and then exceeded the result — yttrium barium copper oxide reached 92 kelvin within months, above the boiling point of liquid nitrogen, replacing an expensive cryogen with a cheap one — citations exceeded a thousand within twelve months, and Bednorz and Müller received the 1987 Nobel Prize, arguably the shortest interval on record between publication and Nobel recognition [ 5 ] . Cuprate superconductivity has since been measured above 130 kelvin at ambient pressure, and the mechanism pairing electrons in these materials is still not settled thirty-nine years later — the opposite situation from BCS metals, where the phenomenon and the mechanism arrived, eventually, together.