Femtosecond degenerate and nondegenerate pump-probe experiments in bulk GaAs below the band gap

Detection of efficient carrier capture in ultrathin InAs/GaAs layers using a degenerate pump–probe technique

By analysing the carrier dynamics based on the rate equations and the change of the refractive index due to the efficient carrier capture, we have calculated the carrier capture process in the InAs/GaAs system detected by a simple degenerate pump–probe technique. The calculated results are found to be in good agreement with the experimental findings. Our results indicate that this simple techni...

Femtosecond real-time pump–probe imaging spectroscopy

Below-band-gap waveguiding behaviors of a weakly index-guided GaAs/AlGaAs quantum well laser

We report the reduced waveguiding efficiency for the signals around 1560 nm as the injection current of an GaAs/ AlGaAs multiple quantum well laser diode (lasing wavelength at 840 nm) with a ridge-loading waveguide configuration increased. This reduction trend stopped when the injection current reached the threshold condition of the laser diode. The decreased waveguide transmission and the more...

Fragmentation of H2-molecules studied with laser-induced Coulomb explosion imaging and femtosecond pump-probe experiments

We report on the experimental realisation of time-resolved coincident Coulomb explosion imaging of H2-fragmentation in 10 W/cm laser fields. Combining a high-resolution ‘reaction microscope’ and a fs pump-probe setup, we map the motion of wave packets dissociating via oneor two-photon channels, respectively, and observe two region of enhanced ionization in accordance with earlier theoretical pr...

Delay control in attosecond pump-probe experiments.

The time delay between the pump and probe pulses in attosecond time-resolved experiments, such as attosecond streaking, is commonly introduced by splitting and recombining the two pulses in an interferometer. This technique suffers from instability in the optical path lengths of the two arms due to mechanical vibration of the optical elements and fluctuating environmental conditions. We present...