Superconducting material made from lutetium hydride is seen potential to revolutionize Energy Efficiency

A research team from the University of Rochester, in a historic feat, created a superconducting material that is capable of operating at extreme temperatures but with less pressure, which is beneficial for various practical applications. The material exhibits superconductivity at 69°F and 10 kilobars (145,000 pounds per square inch (psi) of pressure derived from a nitrogen-doped lutetium hydride (NDLH).

Ranga Dias, assistant professor at UR Mechanical Engineering and Physics who led the team said, “With this material, the dawn of ambient superconductivity and applied technologies has arrived”.

In superconducting materials, electrical resistance vanishes and magnetic fields that are expelled pass around the material. This ability is an advent to power grids that transmit electricity without loss of energy; frictionless, levitating high-speed trains; more affordable medical imaging and scanning techniques such as MRI and magnetocardiography; faster, more efficient electronics for digital logic and memory device technology; and tokamak machines that use magnetic fields to confine plasmas to achieve fusion as a source of unlimited power.

Dias and his team—Nathan Dasenbrock-Gammon, Elliot Snider, Raymond McBride, Hiranya Pasan, and Dylan Durkee — listed as co-lead authors studied properties of lutetium, nitrogen, and hydrogen. Such led them to determine Lutetium being highly localized, fully-filled 14 electrons in its f orbital configuration, can suppress phonon softening and enhance the electron-phonon coupling, features needed for superconductivity to take place at ambient temperatures.

Their key concern, however, it on how to stabilize the material to lower its required pressure. The team then considered nitrogen and its properties to address such a gap. Dias tested the ability of nitrogen to stabilize lutetium by creating a gas mixture that is 99% hydrogen and 1% nitrogen. They placed the mixture in a reaction chamber with a pure sample of lutetium and allowed the components to react for two to three days at 392°F.

Results are remarkable as the lutetium-nitrogen-hydrogen compound when compressed in a diamond anvil cell showed changes from a “lustrous bluish color” to pink at the onset of superconductivity, and then to a bright red non-superconducting metallic state.

Such findings led Dias and his team to address the question of whether a superconducting material can exist at both ambient temperatures and pressures low enough for practical applications.

 “A pathway to superconducting consumer electronics, energy transfer lines, transportation, and significant improvements of magnetic confinement for fusion is now a reality,” Dias says. “We believe we are now at the modern superconducting era.”  

Current endeavors of the team are focused on developing the possibility of training machine-learning algorithms with the accumulated data from superconducting experimentation in his lab to predict other possible superconducting materials – in effect, mixing and matching from thousands of possible combinations of rare earth metals, nitrogen, hydrogen, and carbon.

One of his co-authors, Keith Lawlor is currently working on developing algorithms and making calculations using supercomputing resources available through the University of Rochester’s Center for Integrated Research Computing, for the said future project.