A research team led by Prof. Zhang Jinglei from the Hefei Institutes of Physical Science, Chinese Academy of Sciences, has discovered that the trilayer nickelate La4Ni3O10-δ displays a nearly isotropic upper critical field under high pressure. This finding advances the understanding of the superconducting mechanism in nickel-based materials.
The property is unusual because many superconductors have directional dependence in their critical fields. The near isotropy suggests a unique pairing mechanism in this compound, potentially simplifying models for theoretical physicists.
The team used high-pressure electrical transport measurements to probe the material's response. The upper critical field remained consistent across different orientations, a rare characteristic among nickelate superconductors.
These results could guide the synthesis of new nickel-based superconductors with higher transition temperatures. The work deepens the comparison between nickelate and cuprate superconductors, two families central to condensed matter physics.
While promising, the study does not yet explain the material's pairing glue or confirm room-temperature potential. Further spectroscopic work is needed to validate the microscopic mechanism.