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In this work we present two simple and interactive web-based activities for introducing students to the concepts of uncertainties in measurements. These activities are based on the real-time construction of histograms from students measurements and their subsequent analysis through an active and dynamic approach. Fil: Budini, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina Fil: Giorgi, S.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Física; Argentina Fil: Sarmiento, L. M.. Universidad Tecnológica Nacional; Argentina Fil: Cámara, C.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Física; Argentina Fil: Carreri, R.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Física; Argentina Fil: Gómez Carrillo, Sandra Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina

In this paper, we formulate a quantum jump approach associated with single fluorescent systems whose radiative decay is defined by a Lindblad-like equation with a memory kernel. We base our results in a generalized Born-Markov approximation, which allows us to get our results from a full microscopic description. In the weak-laser-excitation regime, the photon-emission process can be described through a delay function, which in a natural way provides the basis for unravelling the dynamics in terms of a stochastic density matrix. As in the Markovian case, the stochastic dynamics consists in periods where the evolution is smooth and non-unitary, interrupted at random times where the photon-detection events produce a sudden change in the system state. The phenomenon of non-Poissonian intermittent fluorescence induced by complex environments (Budini 2006 Phys. Rev. A 73 061802) is analysed in the context of this approach.

We assume that the origin of decoherence of non-classical motional states of a trapped ion is due to the coupling of the vibronic modes with classical stochastic electric fields and to the finite lifetime of the electronic levels. Working in the dressed basis of the effective two-level Hamiltonian, we show that these interactions lead to a dispersive-like decoherence dynamics. The numerical results agree with the experimental data reported by Meekhof et al.

A class of Langevin-like equations (non-Markovian processes) are studied in the presence of non-natural boundary conditions. Exact results for all cumulants and the corresponding Kolmogorov hierarchy of distributions are given in terms of our functional approach we previously reported (1997 J. Phys. A: Math. Gen. 30 8427). The generalized Wiener processes - on finite domains - are completely characterized for reflecting and periodic boundary conditions. Some examples are given to show the behaviour of the moments and the probability distributions for different noises. The interplay between the boundary conditions and the structure of the noises is also pointed out.

For a quantum open system the so-called Schr?dinger-Langevin picture has been revisited. In a second-order perturbation it is shown that a non-Markovian evolution for the stochastic state vector leads to a dissipative generator which has a Kossakowski-Lindblad form. In this context it is possible to analyse the completely positive condition. The equivalence of this picture with the trace-out technique in the weak coupling approximation has been proved.

Langevin-like equations have been studied in the presence of arbitrary noise. The characteristic functional of the generalized Langevin process has been built up. Exact results for all cumulants are given. Particular stress has been put on the Campbell, dichotomous and radioactive decay noises. Transient relaxation, susceptibility and diffusion constants for different (noisy) media have been sketched in order to exemplify the theory. The generalized Ornstein - Uhlenbeck and Wiener processes have been completely characterized. The generalized Kubo oscillator has been worked out and all its 1-time moments have been calculated for different noise structures.

The nickel-induced crystallization of hydrogenated amorphous silicon (a-Si:H) is used to obtain large grained polycrystalline silicon thin films on glass substrates. a-Si:H is deposited by plasma enhanced chemical vapour deposition at 200 °C, preparing intrinsic and slightly p-doped samples. Each sample was divided in several pieces, over which increasing Ni concentrations were sputtered. Two crystallization methods are compared, conventional furnace annealing (CFA) and rapid thermal annealing (RTA). The crystallization was followed by optical microscopy and scanning electron microscopy observations, X-ray diffraction, and reflectance measurements in the UV region. The large grain sizes obtained – larger than 100 μm for the samples crystallized by CFA – are very encouraging for the preparation of low-cost thin film polycrystalline silicon solar cells.