Probing deep glassy states with ultrastable polymer glass

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Since Anderson's now famous quote (Science, 1995)  that the "The deepest and most interesting unsolved problem in solid state theory is probably the theory of the nature of glass and the glass transition." interest in this area has continued to grow. Recent experimental and theoretical breakthroughs have brought us tantalizingly close to a new level of understanding.  The decades of discussion about whether an "ideal" glassy state exists have been brought to the forefront once more.  On the theory side, a new theory demonstrates without question that  (in infinite dimensions) there is a real phase transition to an ideal glass state. On the experimental side, the discovery that glasses produced by physical vapour deposition can show a kinetic stability (they can be heated significantly above the glass transition temperature before rejuvenating to a supercooled liquid)  which suggests the materials are similar to those that have been aged for thousands or even millions of years. These new extreme amorphous materials provide a mechanism to produce near-ideal glasses without having to age for geological times. Previous work in this area has focused on molecular glasses, and metallic stable glasses have also been prepared and studied. We have recently developed and demonstrated a technique to reliably and reproducibly make stable glasses of polymeric materials. These materials differ from all other previous classes of materials in two key ways. First, and of tremendous practical and fundamental importance, most polymers do not have a crystalline ground state.  This means that avoiding crystallization is trivial compared to other materials. Second, these materials contain an additional parameter that can be tuned- the polymerisation index N. We currently have a significant competitive advantage and the proposal will take full advantage of that. We will compare polymer stable glasses produced by physical vapour deposition (PVD) to similar materials that have been rejuvenated into an equilibrium liquid, quenched to a glass, and aged (for accessible times). This will allow us to determine how well a PVD sample truly mimics one that is aged in the glassy state. We will study local relaxation processes in PVD polymer glass using both local and facility based techniques. We will use our group's 15 years of  experience in studies of surface mobility in glasses to make comparative studies of stable and normal glass surfaces. Through these studies we will be able to determine the best way to make the most stable glasses possible. The study of these extreme amorphous materials that can not be made by nature promises to not only dramatically increase our understanding about glassy materials but also pave the way to new advances in soft electronics, pharmaceuticals, gas membranes, and even polymer batteries. HQP involved in these studies will be well equipped for either academic or private sector opportunities in physics, chemistry, or engineering fields.