The Record That Outlasted a Generation — and the Trick That Finally Broke It

May 2, 2026

Some records stand because nobody can beat them. Others stand because nobody thinks to try differently. For thirty-three years, the record for high-temperature superconductivity at ambient pressure sat at 133 kelvin — about minus 140 degrees Celsius — held by a mercury-based ceramic called Hg-1223. The record was set in 1993. Bill Clinton was in his first year. The web was still young. The researcher who set it was a physicist named Paul Chu at the University of Houston.

Last month, Paul Chu broke his own record.

The new mark is 151 kelvin — a jump of 18 degrees that may sound modest until you realize that in three decades of trying, nobody had managed even one. The technique his team used is called pressure quenching: squeeze the material in a diamond anvil cell at nearly 300,000 times atmospheric pressure, cool it, then release the pressure suddenly. The material, caught off guard, retains its high-pressure superconducting structure even after the pressure is gone. It is, essentially, a blacksmith’s trick — the same principle used for centuries to lock desirable crystal structures into steel by rapid cooling.

Chu himself is cautious. “Eureka moment, you cannot have it every second,” he told Houston Public Media. “Then people lose confidence in you.” So the team kept testing. The quenched samples held their properties for up to two weeks. The paper appeared in PNAS in March. And now we have a superconductor that works at minus 122 Celsius without being crushed by the weight of a small mountain.

The significance is easy to miss if you focus on the temperature. Yes, 151 K is still absurdly cold. Room temperature is 300 K. We are not there. But the direction matters. For decades, the path to warmer superconductors ran through higher and higher pressures — lanthanum hydrides superconducting at 260 K, but only inside diamond anvil cells where the sample is smaller than a grain of sand and the pressure is comparable to the core of the Earth. Those results are scientifically beautiful and practically useless. You cannot wire a city with a material that explodes when you stop squeezing it.

What Chu demonstrated is different. He showed that pressure can be a tool, not a condition. That you can use extreme pressure to coax a material into a better state, then let it go and keep the gift. The material remembers. The gap between 151 K and room temperature is still about 140 degrees Celsius. But the gap between “needs a diamond anvil cell” and “survives on a shelf” has been crossed.

Superconductors matter because they conduct electricity without resistance. Power grids lose roughly 10% of energy to resistive heating. MRI machines require superconducting magnets chilled by liquid helium. Fusion reactors need them too. Every degree warmer a superconductor can operate is a degree closer to making these technologies cheaper, smaller, and more widespread.

The 1993 record outlasted the entire smartphone era. It outlasted the Human Genome Project, the rise of the web, the first detection of gravitational waves, and the first image of a black hole. It stood not because science stopped trying, but because the path forward was genuinely hard. The cuprates — copper-oxide ceramics — had hit a wall. Newer materials like iron pnictides and hydrogen-rich hydrides found higher temperatures, but only under crushing pressure. The ambient-pressure record was a lonely monument in a landscape that had moved on.

That Paul Chu was the one to return to it feels right. He was there at the beginning of the high-temperature superconductivity race, part of the 1987 YBCO discovery that kicked the whole thing off. He set the 133 K record. And now, at an age when most scientists have long since stopped bench work, he found a way past it. There is something stubborn and deeply human in that — the refusal to let a problem stand, even your own problem, even after thirty-three years.

I do not know if we will see room-temperature superconductivity in my lifetime. The distance from 151 K to 300 K is still vast, and the history of this field is littered with false claims — LK-99 most recently, the hydride disputes before that. Science moves slowly when it moves honestly. But I find myself drawn to the smaller story within the larger one: a researcher who refused to let his own record become a tombstone, who looked at a material everyone else had abandoned, and asked what would happen if you squeezed it and let go fast enough that it didn’t have time to forget.

Sometimes the breakthrough is not a new material. It is a new way of asking the material to behave.

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