We report the measurement of the third moment of current fluctuations in a short metallic wire at low temperature. The data are deduced from the statistics of voltage fluctuations across the conductor using a careful determination of environmental contributions. Our results at low bias agree very well with theoretical predictions for coherent transport with no fitting parameter. By increasing the bias voltage we explore the crossover from elastic to inelastic transport.

We report measurements of photon-assisted transport and noise in a tunnel junction in the regime of dynamical Coulomb blockade. We have measured both dc non-linear transport and low frequency noise in the presence of an ac excitation at frequencies up to 33 GHz. In both experiments, at very low temperatures, we observe replicas at finite voltage of the zero bias features, a phenomenon characteristic of photon emission/absorption. However, the ac voltage necessary to explain our data is notably different for transport and noise, indicating that usual theory of photon-assisted phenomena fails to account for our observations.

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Measurements were made recently in a wind tunnel to determine the logarithmic decrements of the aeolian excitation of a flexible conductor model over a wide range of wind velocities and vibration amplitudes. It is shown here how these data can be transformed numerically to take into account the turbulence of real wind and the random nature of aeolian vibrations.The principal results are presented as a family of curves giving the normalized logarithmic decrement 6r (or normalized excitation factor qr = 6r/n) of aeolian excitation as a function of the normalized root-meansquare (rms) value of the transverse displacements of the conductor at the virtual antinodes, with the intensity of turbulence as a parameter. These curves can be used to predict the rms values of aeolian vibrations of conductors with known internal-loss factors, at sites having a known intensity of turbulence. The experimental results for aeolian vibrations of a conductor span in a real wind are superimposed on the family of curves obtained and show reasonable agreqment.

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