Researchers from Harvard revealed last month that they were able to create the first and only known metallic hydrogen. This material was discovered to be a superconductor of electricity as it does not have any resistance even at room temperature.
The creation of this type of superconductor is the culmination of all the work and research conducted by scientists in the last eight decades, and the metallic hydrogen was considered to be the holy grail of physics involving high-pressure.
The researchers were able to only create one sample at the time when the discovery was announced, which was stored in a lab in temperature conditions of almost absolute zero enclosed in a diamond vice. However, it seems that the metallic hydrogen sample has disappeared.
According to Isaac Silvera, a Harvard professor of natural sciences and one of the researchers involved in the initial experiment, the sample was either misplaced meaning that it could be located somewhere at room temperature and pressure, or it just degraded and turned back into its natural state of gas.
The researchers revealed that the metallic hydrogen was created through an experiment involving compressing hydrogen atoms in a diamond anvil. The anvil was used to exert high levels of pressure on the atoms, up to 495 gigapascals, causing them to compress and form the metallic form of hydrogen. However, it seems that the diamond vice was destroyed in the process, which was discovered by measuring the pressure of the system with a low-pressure laser.
As the researchers have not been able to locate the missing sample of the material, they are now trying to recreate their first experiment, by compressing more hydrogen atoms in the same manner. The initial discovery was met with some degree of skepticism from other scientists who also performed similar experiments.
These skeptical scientists were mostly critics of how the Harvard scientists measured the pressure they achieved, as they relied on imprecise calibration and conducted only one measurement of the sample at its highest point of pressure. Therefore, this makes it difficult to know how the pressure shifted over the duration of the experiment and the lifespan of the sample.
What do you think about the disappearing sample of metallic hydrogen?
Image source: Isaac Silvera