The Dawn Of A New Era In Superconductor Materials

Researchers describe a nitrogen-doped lutetium hydride (NDLH) that displays superconductivity at 69 °F and 10 kilobars (145,000 pounds per square inch, or psi), of pressure in an article that was published in Nature.

The advent of ambient superconductivity and applicable technologies has come, according to associate professor of mechanical engineering and physics Ranga Dias.

Although atmospheric pressure at sea level is about 15 psi, 145,000 psi may still seem like a very high pressure, but strain engineering methods are frequently used in chip production, for example, and integrate materials kept together by even higher internal chemical pressures.

This development in condensed matter physics has been the focus of research for more than a century. Electrical resistance disappears, and magnetic fields that are emitted travel around the superconducting substance, which is one of their two main characteristics. These compounds might allow:

Electricity transmission networks that don't lose up to 200 million megawatt hours (MWh) of the energy currently lost due to cable resistance

Levitating, frictionless high-speed trains

Less expensive medical imaging and screening methods like magnetocardiography and MRI

Electronics with increased speed and efficiency for digital logic and memory device technology

Tokamak devices that confine plasmas using magnetic fields to accomplish fusion as an infinite source of power

The Dias team has previously published articles in Nature and Physical Review Letters describing the creation of two materials, carbonaceous sulfur hydride and yttrium superhydride, which are superconducting at 58° Fahrenheit/39 million psi and 12° Fahrenheit/26 million psi, respectively.

Given the significance of the new finding, Dias and his team took unusual measures to record their work and fend off critique that emerged after the previous Nature paper, which resulted in the journal's editors retracting the article. According to Dias, the earlier article has been resubmitted to Nature with fresh data that supports the earlier research. The new information was gathered in the open, in front of scientists who witnessed the superconducting shift firsthand, at the Argonne and Brookhaven National Labs. The new study has adopted a similar strategy.

Five graduate students in Dias's group are named as co-lead authors: Nathan Dasenbrock-Gammon, Elliot Snider, Raymond McBride, Hiranya Pasan, and Dylan Durkee. Everyone in the company participated in carrying out the tests, according to Dias. "It was really a team endeavor,"

At superconductivity and beyond, there is a "startling optical change."

Researchers have recently discovered an intriguing "working formula" for making superconducting materials, which involves combining rare earth metals with hydrogen, followed by adding nitrogen or carbon. Technically speaking, rare earth metal hydrides take the shape of cage-like structures called clathrates, where the rare earth metal ions serve as carrier donors and supply enough electrons to promote the breakup of the H2 molecules. Carbon and nitrogen aid in substance stabilization. The bottom line is that superconductivity can arise at lower pressures.

Researchers have also used other rare earth elements besides yttrium. However, at pressures or temps that are still impractical for uses, the resulting compounds turn superconductive.

Therefore, Dias turned his gaze elsewhere on the periodic chart this time.

"A excellent candidate to test," Dias said of lutetium. Its f orbital arrangement contains 14 highly localized fully-filled electrons, which reduce phonon softening and improve the electron-phonon interaction necessary for superconductivity to occur at room temperature. How will we stabilize this to reduce the needed pressure was the crucial issue. In this situation, nitrogen entered the scene.

According to Dias, nitrogen strengthens the low-frequency optical phonons and, like carbon, has a solid atomic structure that can be used to build a more secure, cage-like lattice within a substance. Because of the durability of this structure, superconductivity can exist at reduced pressures.

A pure sample of lutetium was put in a reaction container with a gas combination made of 99 percent hydrogen and 1 percent nitrogen, and the mixture was allowed to react for two to three days at 392 degrees Fahrenheit.

According to the study, the resulting lutetium-nitrogen-hydrogen compound had a "lustrous bluish hue" at first. A "startling visual change" took place when the compound was squeezed in a diamond anvil cell. It went from blue to pink at the beginning of superconductivity to a brilliant red metallic state that wasn't superconducting.

It was a very vivid crimson, according to Dias. "I was astounded to see such vivid hues. We jokingly proposed the code name "reddmatter" for the substance at this stage after the substance Spock invented in the well-liked 2009 Star Trek film. The cipher moniker endured.

The prior low pressure produced in Dias's lab is nearly two orders of magnitude higher than the 145,000 psi pressure needed to cause superconductivity.

novel superconducting material prediction using machine learning techniques

It has been determined that superconducting material can exist at ambient temps and pressures low enough for useful uses thanks to financing from Dias's National Science Foundation CAREER award and a grant from the US Department of Energy.

"A route to superconducting consumer devices, energy transmission lines, transit, and significantly enhanced magnetic confinement for fusion are now a fact," Dias said. We think that the contemporary superconducting age has arrived.

For instance, Dias believes that the development of tokamak machines will advance significantly faster thanks to the nitrogen-doped lutetium hydride. Tokamaks depend on strong magnetic fields produced by a doughnut-shaped enclosure to capture, hold, and spark super-heated plasmas rather than using strong, convergent laser beams to implode a fuel pellet. NDLH "will be a game-changer" for the developing technology, according to Dias, as it generates a "enormous magnetic field" at room temperature.

The potential to combine and match from thousands of different possible combinations of rare earth metals, nitrogen, hydrogen, and carbon is particularly exciting, according to Dias, and involves training machine-learning algorithms with the accumulated data from superconducting experimentation in his lab.

We use a variety of metals in our daily lives for various purposes, so different types of superconducting materials will also be required, according to Dias. "We need more ambient superconductors for various uses, just as we use different metals for different applications."

Keith Lawlor, a co-author, has already started creating programs and performing computations using the supercomputing capabilities offered by the Center for Integrated Research Computing at the University of Rochester.

A center for superconducting elements in rural New York?

Recently, the study team of Dias relocated to a bigger lab on the third level of Hopeman Hall on the River Campus. A degree-granting Center for Superconducting Innovation (CSI) will be established at the University of Rochester, and this is the first stage in that process, according to him.

In order to progress the study of superconductivity, the center would foster an environment that would attract new academics and researchers to the university. The pool of scholars in the area would grow as a result of the trained pupils.


This is a significant achievement. Even now, the work may very well be commercial in an unusual, extremely tiny niche.

More is still to come. The (first?) fundamental equations are at reach right now. As already mentioned, efforts are being made to discover even more recipes for an increasing number of uses.

But as of right now, this is not a large volume transmission line option. There are still unknown bugs, factors, and circumstances. The extent of this is the operational lab section.

It happened in the past. We congratulate you and express some awe at the ingenuity, invention, and brain growth that have brought the discipline this far. With such a talented group, the idea for a superconducting center is now very promising.

Just one more. Congratulations!