Pulsed laser synthesis of functional nanomaterials

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On the nanometer scale (1000 times thinner than a human hair) the properties of materials can be very different to those we are familiar with. Nanotechnology is the utilisation of these, often superior, properties for the technological advancement of mankind and may be the driving force behind an industrial revolution in the 21st century, making commonplace a wide variety of high-tech devices - everything from miniature computers to labs on a chip that can rapidly screen people for explosive residues as they go through airport security. As nanotechnology ramps up over the next decade, expectations are high that demand for high-tech materials with length on the nanometer scale will skyrocket as well, leading to big profits. However, before these nanomaterials can become dominant in the marketplace cheap, low temperature, large-scale methods for production are required. Also, methods that involve the materials assembling themselves, rather than expensive and time consuming patterning, will become more important for commercial activities. Excimer lasers are a source of invisible, ultra-violet, light which deliver pulses with durations of around a hundred millionths of a second. These very short pulses still contain lots of energy, however, so the power supplied during the pulse can be similar to the output of a power station! Focused laser light with short wavelengths is absorbed in a thin surface region, for the majority of materials, allowing melting and vaporisation of a wide variety of materials placed at the focal point. This forms the basis of a very versatile material deposition and modification system. This research would concentrate on new techniques for using these high power, short pulsed, lasers for the production of technologically relevant nanomaterials, such as nanofoams, nanocoils and nanotubes.