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We present a theoretical model describing the photo-electrical response of a system composed of quantum dots embedded in a dielectric matrix. The model is based on the non-coherent rate equations and the Transfer Hamiltonian formalism. The self charge was included. Within this methodology, the response of the system only depends on fundamental material parameters and its geometry. Transport through several quantum dot configurations was simulated obtaining current-voltage curves in dark and illuminating conditions for three different scenarios: single one quantum dot and two quantum dots in parallel and serial configurations. Despite the simplicity of the model, it has been used to reproduce successfully experimental results., 11 figures

We present a model of electron transport through a random distribution of interacting quantum dots embedded in a dielectric matrix to simulate realistic devices. The method underlying the model depends only on fundamental parameters of the system and it is based on the Transfer Hamiltonian approach. A set of non-coherent rate equations can be written and the interaction between the quantum dots and between the quantum dots and the electrodes are introduced by transition rates and capacitive couplings. A realistic modelization of the capacitive couplings, the transmission coefficients, the electron/hole tunneling currents and the density of states of each quantum dot have been taken into account. The effects of the local potential are computed within the self-consistent field regime., 19 pages, 10 figures. arXiv admin note: text overlap with arXiv:cond-mat/0511652 by other authors

A transport methodology to study the electron transport between quantum dots arrays based in Transfer Hamiltonian approach is presented. The interactions between the quantum dots and between the quantum dots and the electrodes are introduced by transition rates and capacitive couplings. The effects of the local potential are computed within the self-consistent field regime. The model has been developed and expressed in a matrix form in order to make it extendable to larger systems. Transport through several quantum dot configurations have been studied in order to validate the model. Despite the simplicity of the model, well-known effects are satisfactorily reproduced and explained. The results qualitatively agree with other results obtained using more complex theoretical approaches.

Investigation at a $��$--factory can shed light on several debated issues in particle physics. We discuss: i) recent theoretical development and experimental progress in kaon physics relevant for the Standard Model tests in the flavor sector, ii) the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled kaon states, iii) the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and eta/eta$^\prime$ mesons, iv) the contribution to understand the nature of light scalar mesons, and v) the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We also report on the $e^+ e^-$ physics in the continuum with the measurements of (multi)hadronic cross sections and the study of gamma gamma processes., 60 pages, 41 figures; added affiliation for one of the authors; added reference to section 6

The measurement of epsilon'/epsilon has left open several theoretical problems, the most important of which is an accurate calculation of the relevant hadronic matrix elements. Here we study the possibility of relating epsilon' to CP violation in charged K-> 3 pi, which can provide information on the reliability of such calculations. We discuss the role of final state interactions and the main sources of uncertainties. We find that the measurement of Delta g_C in K-> 3 pi is a crucial consistency test for the Standard Model calculations of epsilon'. Valuable information can be deduced also from other observables., Invited talk at 39th Rencontres de Moriond, Electroweak Interactions and Unified Theories, La Thuile, Aosta Valley, Italy, March 21st-March 28th, 2004

The mass of the strange quark is determined from SU(3)-breaking effects in the tau hadronic width. Compared to previous analyses, the contributions from scalar and pseudoscalar spectral functions, which suffer from large perturbative corrections, are replaced by phenomenological parametrisations. This leads to a sizeable reduction of the uncertainties in the strange mass from tau decays. Nevertheless, the resulting m_s value is still rather sensitive to the moment of the invariant mass distribution which is used for the determination, as well as the size of the quark-mixing matrix element |V_us|. Imposing the unitarity fit for the CKM matrix, we obtain m_s(2 GeV)=117+-17 MeV, whereas for the present Particle Data Group average for |V_us|, we find m_s(2 GeV)=103+-17 MeV. On the other hand, using an average of m_s from other sources as an input, we are able to calculate the quark-mixing matrix element |V_us|, and we demonstrate that if the present measurement of the hadronic decay of the tau into strange particles is improved by a factor of two, the determination of |V_us| is more precise than the current world average., 25 pages, 1 eps figure

We update the constraints on the right-handed $W_R$ gauge boson mass, mixing angle $\zeta$ with the left-handed $W_L$ gauge boson, and other parameters in general left-right symmetric models with different mechanisms of CP violation. Constraints mostly independent of any assumption on the quark sector are obtained from a re-analysis of muon decay data. Estimates of the left-right hadronic matrix elements in the neutral kaon system and their uncertainties are revised using large $N_c$ and Chiral Perturbation Theory arguments. With explicitly given assumptions on the long-distance $(\Delta S=1)^2$ contributions to the $K_L-K_S$ mass difference, lower bounds on $M_{W_R}$ are obtained. With the same assumptions, one also gets strong upper bounds from the CP-violating parameter $\epsilon_K$, for most of the parameter space of left-right models where the right-handed third family does not contribute in CP-violating quantities., Comment: 17 pages, latex