Nanowires semimetal-semiconductor transition

Nanowire systems have attracted a great deal of attention recently due to their technological potential They are of fundamental interest because they exhibit unique quantum confinement effects. In this article, advances in the fabrication of nanowires via template-assisted and laser-assisted approaches are reviewed. The structure and characteristics of different nanowire systems are discussed. To understand and predict the unusual properties of nanowires, we have developed a generalized theoretical model for the band structure of these onedimensional systems. A unique semimetal-semiconductor transition that occurs in bismuth nanowires is described. Transport measurements on bismuth and antimony nanowires illustrate that these novel materials are very different from their bulk counterparts. A transport... 

Fig. 16. Schematic illustrating the semimetal-semiconductor transition in nanowires made of semimetals (a) bulk semimetals with a band overlap between the electrons and the holes, (b) nanowires with the critical wire diameter dc where the band overlap vanishes, and (c) nanowires with diameters smaller than dc, exhibiting a bandgap between the conduction and valence bands.

Semimetallic nanowires carrier density, 190-191 schematic of transition, 189 semimetal-semiconductor transition, 188-191 Separations... 

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