Dense packings of hard particles are useful model for a variety of condensed systems, including granular media, heterogeneous materials, liquid, glassy and crystalline states of matter. This talk focuses on the quest for the general organizing principles and salient characteristics of maximally dense and maximally random jammed packings of anisotropic hard particles, which are respectively the crystalline and glassy states of hard-particle colloids. Under equilibrium conditions, hard particles can self-organize into distinct ordered maximally dense packings via entropy-driven phase transitions. Kepler-type conjectures connecting the geometrical and symmetry characteristics of the particles and the self-organized ordered packing structures have been devised, which have ramifications in the design and fabrication of novel materials. The maximally random jammed packings are special non-equilibrium states of hard-particle colloids that possess hyperuniform quasi-long-range correlations only manifested on large length scales. Such a “hidden” order, identified also other disordered system including the density fluctuations in early universe, non-interacting fermion system, and even chicken retina photoreceptor patterns, can be considered as a universal signature of a new state of matter and has led to the development of disordered photonic materials with large isotropic band gaps.

 

Dr. Yang Jiao received his BS from the Department of Mechanics, Peking University in 2005 and his PhD from Princeton University in 2010. Before joining the faculty at ASU in 2013, he worked as postdoctoral research associate in the Physical Science in Oncology Center at Princeton. Dr. Jiao’s major research interests include computational materials, soft matter theory, biophysics and discrete geometry. He has published over 50 research articles and review papers in top tier journals including Nature, PNAS, Phys Rev Lett, PLoS Comput Biol. His has received a number of awards including the Summerfield fellowship and the Ray Grimm Prize in computational physics.