Leighton Group Uncover Mechanism Behind Unique Transport Effect in Metallic Delafossite Materials
The class of complex oxide materials known as metallic delafossites are under intense research scrutiny because they are the most conductive oxides known, with spectacular electronic properties. PdCrO2, one of the materials in this class, is unique in that it pairs this ultrahigh conductivity with an exotic form of magnetism known as geometrically frustrated antiferromagnetism. In a recent publication in the Proceedings of the National Academy of Sciences, the Leighton Group in CEMS, working with Oak Ridge National Laboratory, Argonne National Laboratory, and Brigham Young University, focused on an extraordinary effect in PdCrO2 called the anomalous Hall effect. Remarkably, this magnetic effect was found to persist to seven times the magnetic ordering temperature of the material. Using neutron scattering (see figure), the team showed that this is driven by fluctuations of the spins on the Cr ions, generating deep insight into this unique phenomenon. The significance is that through this mechanism even low-temperature magnetic materials could be used in room-temperature applications, broadening the spectrum of available candidates. The work was led by postdoc Yu Tao in CEMS, working with graduate student Pahuni Jain, and former CEMS students Johnny Zhang and Fred Tutt. The work was funded by the Department of Energy through the U’s Center for Quantum Materials.
Read the full publication on the PNAS website or learn more on Kudos.
Learn more about the Leighton Research Group's work at their website.