Bismuth nanowires properties

We use the same approach to classify the different nanostructures for Titania. The term one-dimensional (ID) nanostructures indicate nanocrystals in which elongation only in one direction is above this threshold (about 10 nm). This class of ID nanostructures comprises different types of nano-ordered materials, such as nanorods, -wires, -coils, -fibers, -pillars (or -columns) and -tubes. We prefer to use the term quasi one-dimensional nanostructures, because often the dimensions are larger than the indicated threshold, although elongation along one main axis still exists. When the diameter of the nanorod, nanowire or nanotube becomes smaller, there is often a significant change in the properties with respect to crystalline solids or even two-dimensional systems. A bismuth nanowire is an excellent example, which transforms into a semiconductor, as the wire diameter becomes smaller.145... 

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... 

In a nanowire system, the quantized subband energy enm and the transport effective mass mzz along the wire axis are the two most important parameters and determine almost all the electronic properties. Due to the anisotropic carriers and the special geometric configuration (circular wire cross section and high aspect ratio of length to diameter), several approximations were used in earlier calculations to derive e m and mzz in bismuth nanowires. In the... 

The lower carrier density of the 80-nm nanowires compared to bulk bismuth is due to the smaller band overlap in the former. For the 40-nm bismuth nanowires, the carrier density has a temperature dependence similar to bulk bismuth at high temperatures, but it drops rapidly with decreasing temperature at low temperatures. Because the carrier density is highly dependent on wire diameter, the transport properties of bismuth nanowires are expected to be highly sensitive to wire diameter, as will be shown experimentally in the section temperature-dependent resistivity of nanowires. ... 

Black, M. R., Lin, Y.-M., Dresselhaus, M. S., Tachibama, M., Fang, S., Rabin, O., Ragot, F., Eklund, P. C., and Dunn, B., Measuring the dielectric properties of nanostructures using optical reflection and transmission bismuth nanowires in porous alumina. MRS Symp. Proc. 581, 623 (2000). 

Liu, K., Chien, C. L., Searson, P. C, and Kui, Y. Z., Structural and magneto-transport properties of electrodeposited bismuth nanowires. Appl. Phys. Lett. 73,1436 (1998a). 

Zhang, Z., Sun, X., Dresselhaus, M. S., Ying, J. Y., and Heremans, J., Electronic transport properties of single crystal bismuth nanowire arrays. Phys. Rev. B 61, 4850 (2000b). 

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