Scientists in Canada and the United States have uncovered new clues about the behaviour of nickelate superconductors, an emerging class of materials that could eventually support advances in quantum computing, energy transmission, and medical imaging technologies.
The research, led by scientists at the University of British Columbia (UBC), alongside collaborators at Argonne National Laboratory and the Canadian Light Source (CLS) in Saskatchewan, found that layered nickelates share a common electronic “fingerprint.” The discovery strengthens comparisons between nickelates and cuprates, the copper-based materials long regarded as the benchmark for high-temperature superconductivity.
The findings, published in Nature Physics, offer fresh insight into the microscopic electronic properties that may allow these materials to conduct electricity without resistance at comparatively high temperatures.
Why Nickelates Matter in Superconductivity Research
Superconductors are materials capable of carrying electricity with zero resistance under certain temperature conditions. Their potential applications range from ultra-efficient power grids to advanced MRI systems and next-generation computing technologies.
Most known superconductors operate only at extremely low temperatures, limiting their practical use. For decades, scientists have focused on understanding “high-temperature” superconductors such as cuprates, which function at temperatures significantly warmer than conventional superconductors.
Nickelates, compounds containing nickel-oxygen ions, have emerged as a promising new addition to this field.
“In our recent study, we focused on an exciting new family of superconducting materials: layered nickelates,” said Andrea Damascelli, principal investigator at UBC’s Quantum Matter Institute and senior author of the study.
“Discovering new superconductors is important both for fundamental science and for potential future technologies, including more efficient energy systems, advanced computing, and powerful magnets used in medical imaging.”
Layered Nickelates Show Similarities to Cuprates
Layered nickelates are built from two-dimensional nickel-oxide layers separated by rare-earth or lanthanide layers. Researchers have been particularly interested in them because their structure and magnetic behaviour resemble those of cuprates.
Christine C. Au-Yeung, a graduate student in Damascelli’s research group at UBC and lead author of the paper, said the study was motivated by major unanswered questions surrounding these materials.
“We wanted to identify which electronic states are most important, how they interact with one another, and what role the layered crystal structure plays in enabling superconductivity,” she explained.
The team examined several multilayer nickelate crystals, including La₃Ni₂O₇, a compound known to exist in different structural forms depending on how its atomic layers are stacked.
According to John Mitchell, senior scientist at Argonne National Laboratory, researchers were able to isolate two distinct crystal structures while observing remarkably similar electronic behaviour.
“Despite these structural differences, the most important electronic features remained essentially the same,” Mitchell said.
Mapping the Electronic ‘Fingerprint’
The researchers identified what they describe as a shared electronic “fingerprint” across multilayer nickelates. This fingerprint is known as the Fermi surface — the boundary separating occupied and unoccupied electronic states inside a material.
Its structure is considered crucial because it determines how electrons move and interact, influencing whether superconductivity can emerge.
“We found that multilayer nickelates share a common electronic fingerprint,” Au-Yeung said. “Its shape is extremely important because it tells us how the conducting electrons move through the material, how they interact with one another, and how they may eventually form a superconducting state.”
To study these properties, the team used angle-resolved photoemission spectroscopy, commonly known as ARPES, at the Quantum Materials Spectroscopy Center beamline at the Canadian Light Source.
ARPES allows researchers to directly observe electron movement by measuring both energy and momentum, effectively creating a detailed map of a material’s electronic structure.
“One way to think about it is as a powerful microscope for quantum matter,” Au-Yeung explained. “Rather than taking a picture of atoms, it reveals the electronic states that govern the material’s properties.”
The experimental results were compared with theoretical calculations predicting the electronic structures of different multilayer nickelates, helping researchers interpret the data and identify the origins of key electronic features.
Magnetic Order and Superconductivity
The study also revealed evidence of a magnetic ordering pattern known as a spin-density wave inside multilayer nickelates.
This occurs when electron spins align in an organized pattern throughout the material, affecting how electrons travel.
“The order we observed is strong and coherent enough to result in a Fermi surface reconstruction,” Damascelli said. “That means it reorganizes the way electrons move and produces a clear signature in our ARPES measurements.”
The findings help bridge the gap between surface-sensitive techniques such as ARPES and bulk-sensitive methods like X-ray and neutron scattering, offering a more complete picture of nickelates’ electronic and magnetic behaviour.
Similarities With Copper-Based Superconductors
One of the study’s most significant conclusions is the strong similarity between the electronic states of nickelates and those found in cuprates.
In cuprates, superconductivity is often associated with a “d-wave pairing symmetry” involving specific electron orbitals and oxygen interactions. Researchers found comparable orbital characteristics in nickelates.
“We found a very similar orbital character in the nickelates,” Damascelli said.
While the team cautions that nickelates and cuprates are not identical, the overlap suggests they may share related mechanisms responsible for superconductivity.
“This comparison is especially valuable because it allows us to ask which features are universal to high-temperature superconductivity and which are specific to a particular material family,” Mitchell noted.
Future Research Could Support Advanced Technologies
Researchers say the study could help guide the development of future superconducting materials with improved performance and broader practical applications.
The next phase of research will focus on time-resolved ARPES, a technique capable of tracking electron behaviour on ultrafast timescales using laser pulses.
Scientists hope this approach will reveal how electronic states interact during superconductivity and how magnetic and superconducting states influence one another.
“By applying this approach to layered nickelates, we hope to gain deeper insight into how superconductivity emerges,” Damascelli said.
The work may also contribute to future advances in quantum technologies, energy-efficient systems, and high-performance medical imaging equipment, areas where Canadian research institutions continue to play an increasingly important role in global materials science.
