Observation and theoretical verification of coherent pulse break-up in gallium arsenide quantum well waveguides

Abstract

Coherent pulse propagation and pulse break-up in atomic media1 have been extensively studied. The long dephasing time in atomic media facilitates observation of these phenomena using relatively long pulses. However, such coherent processes have not yet been observed in semiconductors where the phase relaxation times are very rapid. Here we report on our experimental and theoretical investigations showing coherent pulse break-up in a semiconductor waveguide with photon energies that are off-resonance with respect to the exciton. The transmitted pulses through a multiple quantum well waveguide exhibit pulse break-up for large pulse areas and no pulse break-up for small pulse areas.