Size and randomness effects on the temperature-dependent hopping conductivity of nanocrystalline chains

Abstract:

Developing a renormalization group approach, we study the hopping conductivity of nanocrystalline chains with different site energies. Exact calculations show that many parameters including nano-sizes, randomness of grain distributions, lattice distortions, site energies, transition rates, Fermi energy, and temperature influence the conductivity. Some new singular features, for example the frequency shift, the amplitude fluctuations, and the interchange between “peak” and “valley” behavior of the imaginary part of the conductivity can be caused by certain parameters mentioned above, while the interface distortions modulate mainly the overall amplitudes of the conductivity at the whole frequency region.