Pump-probe measurements on bulk InGaAsP optical amplifiers are compared with numerical calculations based on simplified density matrix equations. We find that the gain dynamics is well described by the combined effect of carrier heating, spectral holeburning, and two-photon absorption.

Highly nondegenerate four-wave mixing processes in bulk semiconductor optical amplifiers are analyzed by comparing experimental data at detuning frequencies up to 3 THz with numerical calculations based on semiclassical density-matrix equations. Carrier heating and spectral holeburning are found to be dominant in mediating wave mixing in the THz region and lead to comparable contributions to nonlinear gain suppression in semiconductor lasers.

Spectrally resolved streak camera measurements of picosecond pulses emitted by hybridly colliding pulse mode-locked (CPM) laser diodes are presented in this letter. Depending on the modulation frequency both blue-chirped (upchirped) and red-chirped (downchirped) pulses can be observed. The two different regimes and the transition between them are characterized experimentally and the behavior is explained on the basis of our model for the CPM laser dynamics.

In the Turkish Earthquake Code (TEC) for buildings built in earthquake zones, it is stated that slab gaps greater than 1/3 of the gross area of the storey should be avoided, and that otherwise there will be A2 type irregularity on the plan due to slab irregularities and that the slabs should be taken to be not functioning as rigid diaphragms. In such buildings in 1st and 2nd degree earthquake zones, it is asked to be shown that the slabs of the storey can safely transfer the earthquake forces in their plane to the vertical structural elements. There are similar points in the codes of other countries as well. In this study, the responses of reinforced concrete buildings under earthquake loads were investigated. The earthquake codes of several other countries were analyzed along with TEC and the conditions that it brings for structural irregularities and slab discontinuities were mentioned. In the building models formed for different positions and ratios of the gaps, the results of the analysis made by keeping in mind the effects of the number of storey, beam continuity, earthquake zone, soil type and rigid diaphragm work on the structural system have been given as graphs.

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