ABSTRACTA full and detailed transient space-charge-limited current (T-SCLC) study of a-Si:H p-i-n diodes has been carried out in the time range from 108s to 10s. In the short-time regime, general features of T-SCLC such as the current cusp and the carrier extraction period were observed, and related transport parameters were deduced. Electron emission from deep states was studied by measuring the current transients well beyond the extraction time. The emission time is thermally activated at temperatures higher than 250K and levels off at lower temperatures. The high temperature behaviour places the upper edge of the deep states at 0.42–0.52eV below the conduction band edge, and the attempt-to-escape frequency in the range of 1011-1013Hz. An observed shift of emission time with light intensity is attributed to defect relaxation.
Energetic ion beams are produced during the interaction of
ultrahigh-intensity, short laser pulses with plasmas. These
laser-produced ion beams have important applications ranging from the
fast ignition of thermonuclear targets to proton imaging, deep proton
lithography, medical physics, and injectors for conventional
accelerators. Although the basic physical mechanisms of ion beam
generation in the plasma produced by the laser pulse interaction with
the target are common to all these applications, each application
requires a specific optimization of the ion beam properties, that is,
an appropriate choice of the target design and of the laser pulse
intensity, shape, and duration.
AbstractA simplified analytical model is presented that predicts the depth progress during and the final hole depth obtained by laser percussion drilling in metals with ultrashort laser pulses. The model is based on the assumption that drilled microholes exhibit a conical shape and that the absorbed fluence linearly increases with the depth of the hole. The depth progress is calculated recursively based on the depth changes induced by the successive pulses. The experimental validation confirms the model and its assumptions for percussion drilling in stainless steel with picosecond pulses and different pulse energies.
Correction: Space charge limited release of charged inverse micelles in non-polar liquids