Researchers from several institutions, including A. Chen, F. B. Kugler, and A. Pustogow from the Institute of Physics at the Czech Academy of Sciences, and A. Georges from the Collège de France and the Flatiron Institute, have published a study in the journal Nature Communications. Their work focuses on understanding the behavior of “bad metals,” a class of materials that do not follow the traditional rules of electrical conductivity. This research could have implications for the energy sector, particularly in the development of advanced materials for energy storage and transmission.
The study investigates the electrical resistance of bad metals as they approach a Mott metal-insulator transition, a phenomenon where a material changes from a conducting to an insulating state due to electron-electron interactions. The researchers used nuclear magnetic resonance (NMR) and transport experiments on single crystals of a specific organic conductor to examine this transition. They found that as the temperature increases, the material transitions from a state where electrons behave like independent particles (quasiparticles) to a state where localized magnetic moments dominate.
The researchers observed that the temperature dependence of electrical resistance in bad metals is not driven by the diffusion of electrons, as previously thought, but rather by changes in the electronic compressibility, which is a measure of how the number of electrons in a material changes with its energy. This finding is significant because it challenges the conventional understanding of electrical conductivity in metals and could lead to new ways of designing materials with tailored electrical properties.
The study also compared experimental findings with theoretical calculations based on dynamical mean-field theory, which accurately reproduced the transport data. This comparison revealed how the crossover between quasiparticle-dominated and local moment-dominated regimes is reflected in the temperature-dependent changes of the quasiparticle spectrum. The researchers suggest that these insights could be useful in the development of new materials for energy storage and transmission, where understanding and controlling the electrical properties of materials is crucial.
In summary, this research provides a deeper understanding of the behavior of bad metals and challenges the traditional view of electrical conductivity. The findings could have practical applications in the energy sector, particularly in the development of advanced materials for energy storage and transmission. The study was published in Nature Communications, a peer-reviewed journal that covers all areas of the natural sciences.
This article is based on research available at arXiv.