Chapter 4
Low-Dimensional Metals and Semiconductors
‘Über Halbleiter sollte man nicht arbeiten, das ist eine Schweinerei, wer weiß, ob es überhaupt Halbleiter gibt.’
‘[One should not work on semiconductors, they are a mess.Who knows whether semiconductors exist at all?]’
Wolfgang Pauli
4.1 Dimensionality and Morphology of Nanostructures
Metals (mostly silver and gold) in nanometric dispersions have been known since Roman times. One of the most beautiful examples of the application of these materials is the Lycurgus cup. This masterpiece of glass blowing appears green in reflected light, but red in transmitted light. These peculiar optical properties are characteristic of metal nanoparticles and are result of their electronic structure and their interaction with the surrounding dielectric medium.
Nowadays nanoparticles and other nanostructured material s (i.e. materials the properties of which are determined by structures of nanometre size) are the focus of researchers and engineers. What is the reason for such tremendous popularity? The answer can be very simple: because of unique optical and electronic properties and chemical/structural diversity [1]. Moreover, the enormous diversity of nanoparticles results from their wide-ranging chemical nature, various dispersion possibilities and, most importantly, potential for bulk and surface modification (Figure 4.1) [2]. Furthermore, these properties are equally dependent on the chemical composition of these materials, and on the size ...
