Universal Dynamic Magnetism in the Ytterbium Pyrochlores

          @misc{ pirsa_PIRSA:16050041,
            doi = {10.48660/16050041},
            url = {https://pirsa.org/16050041},
            author = {Hallas, Alannah},
            keywords = {Condensed Matter},
            language = {en},
            title = {Universal Dynamic Magnetism in the Ytterbium Pyrochlores},
            publisher = {Perimeter Institute},
            year = {2016},
            month = {may},
            note = {PIRSA:16050041 see, \url{https://pirsa.org}}
          }
          

Abstract

The ytterbium pyrochlores, Yb2B2O7, are a family of materials with a remarkable diversity in their low-temperature physics. At the heart of their interesting physics is the proximity of their ground states to numerous competing phases. These proximate phases make the Yb pyrochlores very sensitive to perturbations such as pressure and off-stoichiometry. I will present a study of the effects of chemical pressure on the ytterbium pyrochlores, in which substitution of a non-magnetic constituent alters the lattice size and consequently inflicts an internal pressure on the system. We find that although each of Yb2B2O7 (B = Ge, Ti, Sn) exhibits a distinct dipole ordered state, there is a ubiquitous nature to their spin excitations. Furthermore, these spin excitations are highly unconventional in their own right and may hint at a hidden order parameter.