Electron transport in nanoparticle assemblies

The electrical resistance of nanoparticle assemblies in the form of thin films shows semiconductor-like behavior at low temperatures and metal-like behaviour at high temperatures. We show that this resistance behavior is due to the interplay between Coulomb blockade reduced tunneling of electrons between nanoparticles and the thermal expansion of the nanoparticle assembly. We develop a detailed theoretical model that describes the electron transport process and show that the model agrees well with experimental data.