Recent chemical and structural studies of geometrically frustrated magnets, Dirac Semimetals, and topological insulators.

          @misc{ pirsa_PIRSA:15040160,
            doi = {10.48660/15040160},
            url = {https://pirsa.org/15040160},
            author = {Cava, Bob},
            keywords = {Condensed Matter},
            language = {en},
            title = {Recent chemical and structural studies of geometrically frustrated magnets, Dirac Semimetals, and topological insulators.},
            publisher = {Perimeter Institute},
            year = {2015},
            month = {apr},
            note = {PIRSA:15040160 see, \url{https://pirsa.org}}
          }
          

Abstract

Our search for new materials of (hopeful) relevance to materials physics is wide ranging. One of our primary interests is in finding new geometrically frustrated magnets and working on their structure-property relations. In this context in recent years we have found and grown crystals of a new class of pyrochlore magnets based on fluorine instead of oxygen. This chemical difference allows pyrochlores to be made with magnetic transition metals on the “B sites”, and non-magnetic ions on the A sites, which results in stronger magnetic coupling than is seen in the rare earth pyrochlores. This therefore provides the ability to probe magnetic frustration on the pyrochlore lattice at more easily accessible temperatures. Some of our initial work on these emergent materials, NaCaCo2F7 is an example of one of them, will be described. We have also been exploring the edges of the Dirac semimetal materials space and have recently gotten some interesting results on the Dirac semimetal superconductor Au2Pb. I will describe this material and a recent finding in Ca3P2, a material most often encountered in rat poison. Finally, if time permits, I will describe recent results in our search for the perfect topological insulator.