A team of physicists at UNLV’s Nevada Extreme Conditions Laboratory (NEXCL) used a diamond anvil cell, a research device similar to the one pictured, in their research to reduce the pressure needed to observe a material capable of superconductivity at room temperature. Credit: Image courtesy of NEXCL
Less than two years ago, the world of science was stunned by the discovery of a material capable of superconductivity at room temperature. Now, a team of physicists from the University of Nevada Las Vegas (UNLV) have upped the ante once again by reproducing the feat at the lowest pressure ever recorded.
To be clear, this means that science is closer than ever to a usable, replicable material that could one day revolutionize the way energy is transported.
International headlines were made in 2020 for the discovery of superconductivity at room temperature for the first time by UNLV physicist Ashkan Salamat and his colleague Ranga Dias, a physicist at the University of Rochester. To accomplish the feat, the scientists chemically synthesized a mixture of carbon, sulfur, and hydrogen first into a metallic state, and then further into a superconducting state at room temperature using extremely high pressure conditions (267 gigapascals) that you would only find in nature near from the center of the Earth.
Fast-forward less than two years, and the researchers are now able to complete the feat at just 91 GPa, about a third of the pressure initially reported. The new findings were published as a breakthrough article in the journal chemical communications this month.
a super find
Through detailed tuning of the carbon, sulfur, and hydrogen composition used in the original breakthrough, the researchers can now produce a material at a lower pressure that retains its superconducting state.
“These are pressures at a level that is difficult to understand and assess outside the laboratory, but our current track record shows that it is possible to achieve relatively high superconducting temperatures at consistently lower pressures, which is our ultimate goal,” said study lead author Gregory Alexander Smith. , research graduate student at UNLV Nevada Extreme Conditions Laboratory (NEXT). “At the end of the day, if we want to make devices beneficial to society’s needs, then we have to reduce the pressure needed to create them.”
Although the pressures are still very high, about a thousand times higher than what you would experience at the bottom of the Mariana Trench in the Pacific Ocean, they continue to race toward a near-zero goal. It’s a career that is gaining momentum exponentially at UNLV as researchers gain a better understanding of the chemical relationship between the carbon, sulfur, and hydrogen that make up the material.
“Our knowledge of the relationship between carbon and sulfur is advancing rapidly, and we are finding ratios that lead to remarkably different and more efficient responses than were initially observed,” said Salamat, who directs UNLV’s NEXCL and contributed to the study. last study. “Observing such different phenomena in a similar system shows the richness of Mother Nature. There is so much more to understand, and each new advance brings us closer to the precipice of everyday superconducting devices.”
The Holy Grail of Energy Efficiency
Superconductivity is a remarkable phenomenon first observed more than a century ago, but only at remarkably low temperatures that nullified any ideas of practical application. Only in the 1960s did scientists theorize that the feat might be possible at higher temperatures. The 2020 discovery by Salamat and colleagues of a room-temperature superconductor excited the science world in part because the technology supports electric flow with zero resistance, meaning energy passing through a circuit could be conducted infinitely. and without power loss. This could have major implications for energy storage and transmission, supporting everything from better cell phone batteries to a more efficient power grid.
“The global energy crisis shows no signs of slowing down and costs are rising in part due to a US power grid losing an estimated $30 billion annually due to the inefficiency of current technology,” Salamat said. “For social change, we need to lead with technology, and the work being done today is, I believe, at the forefront of tomorrow’s solutions.”
According to Salamat, the properties of superconductors may support a new generation of materials that could fundamentally change the energy infrastructure of the US and beyond.
“Imagine harnessing the power in Nevada and sending it across the country without any energy loss,” he said. “This technology could one day make it possible.”
Reference: “Carbon Content Drives High-Temperature Superconductivity in a Carbonaceous Hydride of Sulfur Below 100 GPa” by G. Alexander Smith, Ines E. Collings, Elliot Snider, Dean Smith, Sylvain Petitgirard, Jesse S. Smith, Melanie White, Elyse Jones, Paul Ellison, Keith V. Lawler, Ranga P. Dias, and Ashkan Salamat, July 7, 2022, chemical communications.
DOI: 10.1039/D2CC03170A
Smith, the lead author, is a former UNLV undergraduate researcher in the Salamat lab and currently a Ph.D. student in chemistry and research with NEXCL. Other study authors include Salamat, Dean Smith, Paul Ellison, Melanie White and Keith Lawler with UNLV; Ranga Dias, Elliot Snider, and Elyse Jones with the University of Rochester; Ines E. Collings with the Swiss Federal Laboratories for Materials Science and Technology, Sylvain Petitgirard with ETH Zurich; and Jesse S. Smith of the Argonne National Laboratory.
