Originally used to define any work done on the molecular scale, nanotechnology is now used broadly, loosely and indiscriminately to refer to many other 'small technology' research areas where the dimension is less than a micron (1,000nm) or so. Nano has become everyone's favourite prefix - put it into Google and you'll get 68 million hits. It has even been seized upon by marketers to sell small products - witness the nano iPod. True nanotechnology, however, concerns the application of materials, devices and systems that are small enough for the laws of quantum mechanics to start to apply, resulting in 'quantum effects'. These manifest themselves in dramatically different properties - such as melting point, elasticity, specific heat, transport and magnetic properties - compared to bulk behaviour. These unique properties generally become apparent as materials approach around 50 to 20nm in scale and below, and make nanotechnology an exciting subject for the future. It is as if the materials community has just been given a whole new set of materials to work with.
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