Chemistry Seminar with Dr. Tai Kong from the University of Arizona at 4:00pm

A significant part of material research’s mission is to explore and understand the physical properties of materials. The magnetic property will be the focus of this talk. In addition to commonly used ferromagnetism, the arrangement of spins can be quite diverse and closely related to other emerging phenomena. Particularly, when competing magnetic interactions are present in a solid, the ground state can be tuned away from a long-range ordering. Competing magnetic interaction can be achieved by having an odd number of nearest-neighbors in the magnetic sublattice, which we call geometrical frustration. Triangular lattice and Kagome lattice are common lattice types that fit in this category. In this talk, I will present other lattice types that host geometrical frustration. A Shastry-Sutherland (SS) lattice can be viewed as a combination of square and triangular motifs. We successfully synthesized BaRE2ZnS5 (RE = rare earth) single crystals where rare earth elements exhibit a SS lattice. The presence and missing of long-range magnetic ordering in BaNd2ZnS5 and BaCe2ZnS5 will be discussed in the context of geometrical frustration, quantum criticality and magnetic dimmers. More lattice types that can potentially host geometrical frustration will be presented at the end of this talk.