Leighton group research unveils the mechanism behind ultrahigh conductivity in new materials

Research published in the journal Nature Communications by the Leighton Group in CEMS provides the first full understanding of the mechanism behind the ultrahigh electrical conductivity of a class of materials called metallic delafossites. The work, led by graduate student Johnny Zhang and collaborators, focuses on a fascinating class of oxides exemplified by PdCoO2. These materials are the most conductive oxides known, achieving higher conductivity than even gold, despite being complex oxides with two-dimensional crystal structures. This collaboration, featuring the groups of Leighton and Birol in CEMS, as well as coauthors in Earth and Environmental Sciences, the Characterization Facility, and the School of Physics and Astronomy, first realized a new approach to crystal growth of these materials, achieving 500X gains in size, and the highest structural and electrical quality yet reported. It was then shown that the key to the ultrahigh conductivity is a “sublattice purification” mechanism, where the insulating atomic layers in these materials absorb the vast majority of the impurities and defects, leaving highly perfect metallic layers in which electrical current flows. 

The work was published on February 15th, 2024, and is free to read at: https://www.nature.com/articles/s41467-024-45239-6. The work was funded by the Department of Energy through the Center for Quantum Materials.