Non-Gaussian fluctuation in the charge transport of Si nanochains

Modeling collective charge transport in nanoparticle assemblies

Mapping the assembled patterns of nanoparticles onto networks (mathematical graphs) provides a way for quantitative analysis of the structure effects on the physical properties of the assembly. Here we review the network modeling of the conduction with single-electron tunneling mechanisms in the assembled nanoparticle films. Simulations of the conduction predict the nonlinear current-voltage curves in different classes of the nanoparticle networks. Furthermore, the numerical analysis reveals how the I(V) nonlinearity is related to the collective charge fluctuations along the conducting paths through the sample, and stresses the role of the topology and quenched charge disorder.

Converting an insulating silicon nanochain to a conducting carbon nanotube by electrical breakdown

Electrical breakdowns of individual silicon nanochains, in which silicon nanoparticles are covered with and connected by oxide alternatively forming nanowires, are studied by in situ transmission electron microscopy using a microprobe system. Individual silicon nanochains can endure a current typically as large as 10(0) nA, and we found that a silicon nanochain can be converted to a nanotube by applying a current as large as 10(1) nA. In the nanotubes, some silicon particles are left. Experimental results suggest that nanotubes are heavily distorted carbon nanotubes, which are formed through the aggregation of contaminating carbon on the nanochain surface and the evaporation of the oxide core due to Joule heating.