Researched
High-Temperature Superconductors
Bednorz and Müller discover copper-oxide superconductors in 1986; YBCO at 93 K (1987) is the first above liquid-nitrogen temperature.
Open in the interactive tree →Until 1986 the record was 23 K. Cuprates, ceramics with copper-oxide planes, reach 133 K at normal pressure (Hg-1223, 1993); in March 2026 a Houston group reported 151 K at normal pressure in a pressure-quenched sample (not yet independently replicated). Why they work is not fully explained after 40 years, and the classical BCS theory does not suffice.