セミナーSeminar

A fine balancing act: mechanisms behind "avalanche" devitrification in deeply supercooled liquids

Glassy, amorphous materials are known to undergo spontaneous, localised structural transformations over time, resulting in the formation of small crystallites. This is known as spontaneous devitrification, and adversely affects physical properties like transparency, solubility and brittleness in a range of industrial applications, from ceramics and optical fibers to pharmaceuticals. In particular, recent work has shown that deeply supercooled liquids exhibit intermittent, collective particle movements known as "avalanches" which strongly correlate with intermittent crystallisation. This talk aims to shed light on the triggering mechanisms behind this "avalanche" devitrification, highlighting the subtle balance between two effects, thermodynamics and mechanical rigidity, which may underpin these unique events. We will focus on Brownian Dynamics simulations of rapidly supercooled quasi hard-sphere fluids, as well as how local transformation of the same packings to a hyperuniform state can drastically alter stability against devitrification.