Physicists have longed to find a material that could easily convey electricity at regular temperatures, an accomplishment that would spare immense measures of energy and reform modern technology, for quite a long time.
Now, after more than a century of waiting, the scientists have reported the discovery of the first room-temperature superconductor.
Sri Lankan Professor, physicist Ranga Dias, an assistant professor of Mechanical Engineering and of Physics and Astronomy, at the University of Rochester in New York, along with Salamat and other collaborators have discovered a superconductor that works at temperatures of about 15° Celsius (59° Fahrenheit), compressing simple molecular solids with hydrogen at extremely high pressures.
Featured as the cover article in the journal Nature, the work was conducted by the lab of Ranga Dias. In setting the new record, Dias and his research team combined hydrogen with carbon and sulfur to photochemically synthesize simple organic-derived carbonaceous sulfur hydride in a diamond anvil cell, a research device used to examine miniscule amounts of materials under extraordinarily high pressure.
The carbonaceous sulfur hydride exhibited superconductivity at about 58 degrees Fahrenheit and a pressure of about 267 billion pascals, about a million times higher than a typical automobile tire pressure. This is the first time that superconducting material has been observed at room temperatures.
“Because of the limits of low temperature, materials with such extraordinary properties have not quite transformed the world in the way that many might have imagined. However, our discovery will break down these barriers and open the door to many potential applications,” said Dias, who is also affiliated with the University’s materials science and high-energy- density physics programs.
To make the superconductor, the scientists had to squeeze the substance between two diamonds to nearly 40 million pounds per square inch. The process produced specks of material about the volume of a single inkjet particle.
Superconductors transmit electricity without resistance, allowing current to flow without any energy loss. But all superconductors previously discovered were cooled, many of them to very low temperatures, making them impractical for most uses. This restriction makes them costly to maintain-and too costly to extend to other potential applications.
“The cost to keep these materials at cryogenic temperatures is so high you can’t really get the full benefit of them,” Dias said.
However, the new material’s superconducting superpowers appear only at extremely high pressures, limiting its practical usefulness.
Previously, the highest temperature for a superconducting material was achieved last year in the lab of Mikhail Eremets at the Max Planck Institute for Chemistry in Mainz, Germany, and the Russell Hemley group at the University of Illinois at Chicago. That team reported superconductivity at -10 to 8 degrees Fahrenheit using lanthanum superhydride.
The team’s results “are nothing short of beautiful,” said materials chemist Russell Hemley of the University of Illinois at Chicago, who was not involved with the research.
The first superconductors observed by scientists lost their electrical resistance only at ultracold temperatures, a few degrees above absolute zero, or minus 459.67 degrees, the lowest possible temperature. In the 1980s, physicists discovered so-called high-temperature superconductors, but even those became superconducting at temperatures far more frigid than those encountered in everyday life.
“You can start with knowing what the good binary systems are and then potentially adding another element to it to get more complex,” said Eva Zurek, a professor of chemistry at the University at Buffalo who performs numerical calculations to predict the behaviour of the high-pressure materials. “And hopefully, this complexity can bring the superconducting critical temperature up or stabilization pressure down.”
Dr. Zurek, who was not involved with the latest research, said carbon was a good third element to add because it formed strong bonds that could potentially keep the material together. “If you release the pressure, then those bonds potentially will not break,” she said.
The experimental results did not fully agree with Dr. Zurek’s computer calculations, which predicted the highest superconducting temperatures at lower pressures. Dr. Dias instead found that the superconducting temperature continued to increase as the pressure rose.
If a room-temperature superconductor could be used at atmospheric pressure, it could save vast amounts of energy lost to resistance in the electrical grid. And it could improve current technologies, from MRI machines to quantum computers to magnetically levitated trains. Dias envisions that humanity could become a “superconducting society.”
Dias says developing materials that are superconducting-without electrical resistance and expulsion of magnetic field at room temperature-is the “holy grail” of condensed matter physics. Sought for more than a century, such materials “can definitely change the world as we know it,” Dias said.
• Faster, more efficient electronics for digital logic and memory device technology
“We live in a semiconductor society, and with this kind of technology, you can take society into a superconducting society where you’ll never need things like batteries again ,” said Ashkan Salamat of the University of Nevada Las Vegas, a coauthor of the discovery.
The next challenge, Dias says, is finding ways to create the room temperature superconducting materials at lower pressures, so they will be economical to produce in greater volume.
However, we, perabeats, as the official media unit of the University of Peradeniya extend our sincere gratitude to Professor Ranga Dias and his research team for bringing such pride to Sri Lanka with such a great victory.
Article By – M.N.F Hilma.