A study that received a lot of attention and in which researchers claimed to have seen the first actual room-temperature superconductor has since been discredited.
The creation of a superconductor that functioned at the unheard-of temperature of 15 degrees Celsius was reported in a paper published by physicist Ranga Dias and his colleagues from the University of Rochester in Rochester, New York. This paper sparked interest, but it also prompted scientists to exercise caution. The substance was a combination of carbon, hydrogen, and sulfur; but, in order for it to conduct electricity without any resistance, it needed to be compressed between the points of two diamonds to a pressure that was 2.6 million times greater than that of the atmosphere.
Superconductors are essential to a wide variety of scientific and medical applications because of their ability to transport huge electric currents without generating any waste heat. It is possible that superconductors will also be essential to the development of future technologies that save energy. However, the majority of superconductors only function at temperatures that are very close to absolute zero (–273 degrees Celsius). Physicists have only in recent years been successful in employing high-pressure anvils to get some to work at temperatures exceeding 0 degrees Celsius.
According to the retraction notice that was published2 on September 26th, the team led by Dias “used a non-standard, user-defined approach” in order to remove the noise from the experimental data that was displayed in two figures. “The specifics of the process were not stated in the study, and as a result, the reliability of the background subtraction has since been questioned.” In spite of the objections raised by the study’s authors, the editors of Nature decided to retract the study.
Dias, along with his coworkers, has expressed through a representative that they do not agree with the retraction and that they stand by their results. They intend to resubmit the publication to Nature with the raw-data plots of the figures included this time around. According to the statement, the fact that the retraction was requested does not call into question the “observed physical superconducting state” of the carbon–sulfur–hydrogen material. In addition to pointing to an arXiv publication that was posted3 in 2021 that addresses the problems raised by the researchers and exposes the raw data, it stated that three different teams had duplicated aspects of the results.
Following the publishing of a response4 to the initial study in Nature by physicists Jorge Hirsch of the University of California, San Diego, and Frank Marsiglio of the University of Alberta, Edmonton, Canada, the original paper was retracted. The two individuals had posed a number of concerns with regard to the study, particularly with regard to the two figures that were discussed in the notice of retraction. When the material was cooled below a threshold temperature, they indicated a drop in a property called magnetic susceptibility. This is thought to be a telltale sign of superconductivity because it is a sign that magnetic susceptibility is decreasing. The assertion has been called into doubt by a number of other media as well as by physicists who, at the time of the article’s first publication, were interviewed by the news team at Nature and pointed out some of the same problems.
According to Mikhail Eremets, a physicist at the Max Planck Institute for Chemistry in Mainz, Germany, the decision to abandon the study was “dramatic,” but it was ultimately the right one. According to him, the industry will now be able to put a debate that has lasted for two years behind it. There will be more time for scientists to devote to working on “real stuff.” Eremets’s laboratory has attempted, but been unable to, recreate the results obtained by Dias’s team. Eremets and his co-authors had already made the decision to stop referencing the now-retracted publication before the paper was retracted.