Picosecond laser for surface spectroscopy

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Funds are requested to urgently replace a pulsed laser that is the main component of my research program, and is the central piece of equipment associated with all of my NSERC-funded projects (through Discovery, Engage, CRD, USRA). An average of 10 students use this laser each year, and it operates approximately 450 hours each month. This laser has been well-maintained over the past 14 years, but is increasingly showing signs that it is aging. Its behaviour has already resulted in significant research delays. This is an urgent request to replace this critical component of my research program before it fails altogether.******The laser is used to generate ultra-short pulses of light tunable throughout the mid-infrared region. It enables fundamental studies of material surfaces, especially the interface between minerals (such as silica) or polymers and aqueous solutions. Understanding the structure molecules at such solid-liquid interfaces is of critical importance to environmental and geochemical processes such as rock weathering, erosion, and pollutant transport. Technologies such as DNA microarrays and drug delivery rely on precise control of the surface protonation state and surface charge. Polymers are used to produce many of the objects we encounter in our daily life. While their bulk properties make them stiff or pliable, transparent or opaque, an equal amount of attention goes into tailoring their surfaces to best interact with their intended surroundings. For example, materials such as acrylic are widely used in medical implants as they are strong and lightweight, but their surfaces are not naturally biocompatible. Our research seeks to understand how polymer surfaces are altered on the nanometre scale when they are placed next to liquids such as biological fluids. Surface modification is also important in textile processing, as plasma-treated fibres have increased adhesion to dyes, dramatically reducing or eliminating the need for solvents that are harmful for workers and the environment. Studying charged polymer surfaces also leads to improved understanding of how lightweight insulators withstand weathering for reliable overhead power distribution to Canadian towns and cities. ******This piece of equipment, a sophisticated surface analysis probe powered by the requested picosecond laser, provides many training opportunities for students as they design experiments, and tailoring its output for the particular surface under investigation. Interpreting the results of these experiments in order to extract the sought chemical structural information often entails modelling on various levels and the application of advanced data visualization strategies. The experiments enabled by this equipment therefore further fundamental science with direct short-term applications, and simultaneously train the next generation of scientists and engineers.