Introduction to Nanoscience and Nanotechnology

Chapter 1

Size Matters

1.1 The Fundamental Importance of Size

The aim of this chapter is to instill an intuitive feel for the smallness of the structures that are used in nanotechnology and what is special about the size range involved. As we will see, the importance of the nanoscale is wrapped up with fundamental questions about the nature of matter and space that were first pondered by the ancient Greeks. Three thousand years ago, they led the philosophers Leucippus and Democritus to propose the concept of the atom. These ideas will come around full circle at the end of the book when we will see that modern answers (or at least partial answers—the issue is still hot) are very much wrapped up in nanotechnology.

First of all, let us remind ourselves how small nanostructures really are. This is a useful exercise even for professionals working in the field. The standard unit of length in the metric system is the meter, originally calibrated from a platinum–iridium alloy bar kept in Paris but since 1983 has been defined as the distance that light travels in 1/299,792,458 seconds. For convenience, so that we are not constantly writing very small or very large numbers, the metric system introduces a new prefix every time we multiply or divide the standard units by 1000. Thus a thousandth of a meter is a milli-meter or mm (from the Roman word mille meaning 1000); a thousandth of a millimeter (or a millionth of a meter) is a micro-meter or µm (from the Greek word mikros meaning small). ...