Spin-polarized attractive Fermi gases in one-dimensional (1D) optical lattices are expected to be remarkably good candidates for the observation of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase. We model these systems with an attractive Hubbard model with population imbalance. By means of the density-matrix renormalization-group method, we compute the pairing correlations as well as the static spin and charge structure factors in the whole range from weak to strong coupling. We demonstrate that pairing correlations exhibit quasi-long-range order and oscillations at the wave number expected from the FFLO theory. However, we also show by numerically computing the mixed spin-charge static structure factor that charge and spin degrees of freedom appear to be coupled already for a small imbalance. We discuss the consequences of this coupling for the observation of the FFLO phase, as well as for the stabilization of the quasi-long-range order into long-range order by coupling many identical 1D systems, such as in quasi-1D optical lattices.

In this paper an efficient method to synthesize all-optical synchronous digital finite state machines is suggested. The synthesis is based on the design of purely combinational circuits composed of a cascade of iterative cells that perform the same logical functions of the corresponding synchronous Finite State Machine (FSM). This allows high bit rates and a high degree of modularity, so an easy integration of the circuit is possible. These characteristics make the method suitable to be adopted in a photonic environment in which clocked digital memory elements are still a critical aspect.

The performance of a GaAs detector based on a pixel matrix architecture is evaluated experimentally. Several spectral distributions have been obtained for a single GaAs pixel and compared with that of a reference Si sample in order to determine the charge collection efficiency and the energetic resolution. The obtained results indicate the detector's ability to interact with low-energy X-rays to generate good quality images for high-contrast details

Starting from the Starring and the GIMS networks a new interconnection multihop network called EXSTAR is presented. It has potentialities, in terms of number of users, modularity and performance much higher than Starring, GIMS and other multihop structures. Moreover it still offers a notable simplicity in routing strategies, giving rise to routing processors including only few all-optical gates