Nanowires carrier densities

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

Fig. 17. Calculated total carrier density (electrons and holes) as a function of temperature for bulk 3D bismuth and bismuth nanowires of different diameters oriented along the [0112] direction.

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. ... 

Ballistic transport, 191 Band structures, nanowire calculated subband energies as function of in-plane mass anisotropy, 188 carrier densities, 190-191 dispersion relation of electrons, 185 envelope wavefunction of electrons, 186 grid points transforming differential... 

Schmidt V, Senz S, Gosele U (2007) Influence of the Si/Si02 interface on the charge carrier density of Si nanowires. Appl Phys A 86 187-191... 

Mora-Stao I, Fabregat-Santiago F, Denier B, Bisquert J, Tena-Zaera R, Elias J, Levy-Clement C (2006) Determination of carrier density of ZnO nanowires by electrochemical techniques. Appl Phys Lett 89 203117... 

Measurements of mobility in PS suffer from the fact that the number of free charge carriers is usually small and very sensitive to illumination, temperature and PS surface condition. Hall measurements of meso PS formed on a highly doped substrate (1018 cm3, bulk electron mobility 310 cm2 V-1 s-1) indicated an electron mobility of 30 cm2 V 1 s 1 and a free electron density of about 1013 cm-3 [Si2]. Values reported for effective mobility of electron and hole space charges in micro PS are about five orders of magnitude smaller (10-3 to 10 4 cm2 V 1 s ) [PelO]. The latter values are much smaller than expected from theoretical investigations of square silicon nanowires [Sa9]. For in-depth information about carrier mobility in PS see [Si6]. 

Fig. 15. Calculated effective densities of states for 40-nm bismuth nanowires (solid curve) and bulk bismuth (dashed curve). The zero energy refers to the band edge of bulk bismuth. The nonparabolic effects of the electron carriers are considered in these calculations.

Collectively, the term q GfJApi r is the photocurrent density passed at the planar photoelectrode at short circuit. If a thin nanowire morphology is applied to this exact same semiconductor material and charge-carrier recombination is predominantly in the core of the nanowire (i.e., not in the depletion region), then the photovoltage will follow Equation 5.27 instead ... 

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