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A model which takes into account the main phenomena occurring during the laser-cladding process is proposed. For a given laser power, beam radius, powder jet geometry, and clad height, this model evaluates two other processing parameters, namely, the laser ...
We study the optical properties of strongly photo-excited GaAs/AlxGa1-xAs Quantum Wells in the one-dimensional optical amplifier geometry. One part of our work deals with gain measurements using the "variable stripe length method". We are proposing two new ...
Brillouin gain spectrum measurements in fibres are presented, where a single source is used to generate the pump and probe signals, giving highly reliable results. ...
In this paper we present briefly two possible approaches for modelling the laser cladding process. The first approach is 2D and consists in finding the shape of the molten pool given the fraction of the laser power which is available at the surface of the ...
Spin orientation by optical pumping experiments were undertaken on three strained In0.2Ga0.8As/GaAs QW's with different thicknesses. The results concerning the circular degree of polarization dependence on the exciting energy are very different from well t ...
Internal photoemission (IPE) measurements of the conduction band discontinuities at GaAs/amorphous-Ge interfaces have been carried out at the Vanderbilt Free-Electron Laser (FEL). IPE is a simple and direct measurement capable of unprecedented accuracy. Th ...
A novel configuration is presented here, based on the pump and probe technique, that has the following advantages: 1) few optical elements are required, 2) a single laser source is used, 3) a single fiber end is accessed, 4) only pulsed signals propagate. ...
Brillouin-gain-spectrum measurement along an optical fiber has recently gained a lot of interest owing to its potential for strain monitoring in installed cables and for distributed temperature sensing. We present a method that has the following advantages ...
We used optical pumping by the Vanderbilt free-electron laser and the technique of internal photoemission to measure with high accuracy the conduction-band discontinuity of semiconductor heterojunction interfaces. The experiment is the first application to ...
