Metallic, hydrogen-rich compound found to demonstrate superconductivity at near room temperature
Scientists believe there could be other hydrides or superhydrides with super conducting properties
Scientists at the George Washington University claim to have made significant progress towards creating room-temperature superconductors.
The team says it has found evidence that a metallic, hydrogen-rich compound can demonstrate superconductivity at near room temperature and very high pressures.
Superconductivity is the phenomenon wherein some materials show complete disappearance of electrical resistance when cooled below a 'critical temperature'. This temperature is different for different materials but is usually below 20 degrees Kelvin (-253 degrees Celsius).
The phenomenon was first observed in 1911 in solid mercury. Since that time, scientists have been trying to find a material that demonstrates superconductivity at or close to room temperature. Discovery of such a material would not only enable more efficient use of electricity around the world but would also help create vastly more powerful computers.
In the current study, researchers took miniscule samples of hydrogen and lanthanum, and squeezed them together at high pressures using diamond anvil cells. The resulting material was heated, which created compound LaH10 with entirely new structure.
The team observed the changes in the electrical properties of LaH10 at high pressures and found that its electrical resistivity dropped significantly at temperatures below 260 degrees Kelvin (minus 13 degrees Celsius or 8.3 degrees Fahrenheit) at 180-200 gigapascals of pressure.
In later experiments, the material was found to demonstrate superconducting properties at even higher temperatures, up to 280 degrees Kelvin (6.85 degrees Celsius or 44.3 degrees Fahrenheit).
The team also used X-ray diffraction technique to observe changes in the properties of LaH10 and found evidence of the same phenomenon.
"We believe this is the beginning of a new era of superconductivity," said Russell Hemley, a research professor at the GW School of Engineering and Applied Science.
"We have examined just one chemical system - the rare earth La plus hydrogen. There are additional structures in this system, but more significantly, there are many other hydrogen-rich materials like these with different chemical compositions to explore."
The team hopes to find many other hydrides or superhydrides demonstrating even higher transition temperatures at high pressures.
The findings of the study are published in the journal Physical Review Letters.