Effects of Coulomb interaction on charge transport in a silicon-based nanocluster array

The effects of Coulomb interaction on charge transport in a model of light emission from an array of silicon nanoclusters are studied by Monte Carlo simulations. The array is sandwiched between a p-type and an n-type doped silicon crystals and electrons and holes are driven into the array by an applied electric field. Radiative recombinations of electrons and holes take place near the center of the array producing the emission of red light, and the total emission power is approximately proportional to the current injected into the system. It is found that the carrier-carrier interaction plays a crucial role in charge transport. Specifically, the self-interaction of charges inside each nanocluster is found to be the dominant interaction term for the semiclassical Hamiltonian considered. In addition, it drastically limits the current in the device giving rise to a strong non-linear relation between current and density of free carriers in the doped silicon crystals. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2005