Source | Qubit | Public account QbitAI
After the LK-99 controversy that sparked global heated discussion came to an end, a headline in Nature mentioned "room temperature superconductivity" again.
Although the enthusiasm for superconductivity has not diminished, as it has been falsified time and time again, it is difficult for people not to be cautious about "room temperature superconductivity".
This article in Nature uses the real experience of a researcher to analyze the reasons behind it.
The original title of this article is "Why room temperature superconductivity is always questioned", which seems to be a comment.
But in fact the article is "telling a story", and the protagonist is Ranga Dias, a physicist at the University of Rochester in the United States.
It was the scholar who announced the discovery of a new "room-temperature superconducting material" that caused a packed house at the American Physical Society meeting in March.
The Dias team claims that the material they developed is a hydride called iminolutetium (LuNH), which is said to have "superconducting properties" at 1GPa and 21 degrees Celsius.
Unlike LK99, Dias's paper on LuNH triggered massive doubts after its release.
The experiment failed to reproduce, the author refused to disclose the details of product preparation, and Nature also added a note of "questionable data" to it.
This is not the first time that Dias’s paper has been questioned. The team had previously released a hydride “room temperature superconducting” material, which was eventually withdrawn.
Only one team reproduced "partial success"
Previous retraction experiences may have deepened people's suspicions, but many teams have still tried to reproduce Dias' experiments.
However, the results were not what Dias expected—these replication experiments basically ended in failure.
Two months after the paper was released, Professor Wen Haihu’s research group from Nanjing University published a paper stating that LuNH does not show superconducting properties.
At the same time, many universities and research institutions at home and abroad have also carried out "counterfeiting" on the "superconducting properties" of LuNH.
However, there is a team that claims to have successfully reproduced Dias's results, but the evidence does not seem to be sufficient.
A paper released by the Hemley team at the University of Illinois at Chicago showed that the resistance change of LuNH was observed at around 3°C.
However, professionals say that the resistance change alone is not enough to prove that LuNH has superconducting properties, not to mention there are only four data points in the paper.
Alexander Drozdov, a researcher at the Max Planck Institute in Germany, even said that this result may be due to poor contact.
Regarding the failure of experimental replication, Dias’s explanation was that these teams “did not have enough samples and did not conduct enough tests.” However, Dias did not disclose the experimental plan and sample preparation details in detail.
Not only was the experiment unsuccessful, LuNH was also questioned at the theoretical level.
Lilia Boeri, a theoretical condensed matter physicist at Sapienza University in Rome, told Nature that some researchers have used computers to simulate various arrangements of Lu, N and H atoms, but have failed to observe signs of room-temperature superconductivity.
The author has repeatedly been involved in academic scandals
In addition to the content of the paper itself, Dias’s “record of academic misconduct” may also be an important reason why he is suspected.
According to the Science magazine website, this year someone accused Dias of plagiarizing his doctoral thesis from James Hamlin of Washington University in St. Louis.
It is reported that Dias’s paper has at least 6,300 words (about 21%) that are the same as Hamlin’s paper.
In this regard, Dias said that there was indeed some content that was "not clearly marked with sources", but declined to make further comments.
Dias was accused of academic misconduct, including plagiarism and data falsification.
This includes the "Room Temperature Superconductivity" paper first published by Dias in 2020 (which has been withdrawn).
But after the article was withdrawn, the University of Rochester, where Dias worked, investigated the matter and concluded that "there was no evidence to support these concerns."
Coincidentally, another paper published by Dias in Physical Review Letters (PRL) was also questioned as fraudulent.
PRL commissioned four independent reviewers to investigate the matter, and the findings "convincingly support the allegations of data fabrication/falsification".
Except for Dias himself, all other authors of this paper signed and agreed to withdraw the manuscript, but Dias still insisted that there was no problem with the results.
It is not known whether these academic scandals are real or have hidden secrets, but what is certain is that scientists are becoming more and more cautious about Dias research.
参考链接：
[1]https://www.nature.com/articles/d41586-023-02733-z
[2]https://www.science.org/content/article/plagiarism-allegations-pursue-physicist-behind-stunning-superconductivity-claims