Conductivity claim splits scientists
A world of levitating trains, quantum computers and massive energy savings may have come a little closer, after scientists claimed to have attained a long-sought dream of physics – room temperature superconductivity.
The achievement, announced in the journal Nature, comes with two caveats, however.
The first is that at present, it only works at 10,000 times atmospheric pressure. The second is that the last time members of the same team announced similar findings, they had to retract them amid allegations of malpractice.
Jorge Hirsch, from the University of California, San Diego, said that on the face of it, the achievement was stunning.
‘‘If this is real it’s extremely impressive, groundbreaking, and worthy of the Nobel Prize.’’ But he added: ‘‘I do not think it’s real.’’
His opinion reflects a scientific community that is divided about the announcement.
For more than a century, scientists have known that under certain conditions, certain materials are able to conduct electricity with near-zero resistance, while also exhibiting unusual magnetic properties.
Harnessing this ‘‘superconductivity’’ has revolutionised fields such as medical imaging, where MRI scanners rely on powerful magnets that in turn rely on superconductivity. It has also been used in maglev (magnetic levitation) trains, which slash friction by floating on magnets.
The problem is that to make it work, you have to cool the material to extremely low temperatures – in the case of an MRI machine, to almost
minus 270C. This limits the applications and makes them expensive.
‘‘Room temperature superconductivity would be important as a physical phenomenon by itself,’’ said Siddharth Saxena from the University of Cambridge. He said he and his colleagues would be closely examining the latest research by a team at the University of Rochester in New York.
Peter Edwards, emeritus professor of inorganic chemistry at the University of Oxford, said the claims had clearly ‘‘divided the research community, ranging from outright dismissal to huge excitement’’.
Superconductivity happens when electrons are able to move without the collisions that cause resistance. The
New York team investigated a material called lutetium hydride. Hydrides, materials containing a lot of hydrogen, are in theory a promising candidate for superconductivity.
According to the team, when they compressed the material, it changed colour from blue to pink. As it did, it gained the superconducting properties, and did so at around room temperature.
One reason for the scepticism is that research published by members of the same team in 2020 appeared to show similar results in a different material, but there were discrepancies in the data. The researchers say they were not deliberate, and the findings still hold, but the paper was retracted.