RESUMO
High-resolution amplitude and phase linear spectroscopy of high-quality bulk GaAs are reported. The detailed structure of the observed full complex transmission is consistently explained by polariton effects on the basis of microscopic calculations. The coupled equations for the excitonic polarization and the light field in the slab configuration are evaluated using appropriate boundary conditions for the electromagnetic field and the excitonic wave function without reference to additional boundary conditions for the macroscopic polarization.
RESUMO
Two phase-locked pulses are used to coherently excite excitonic polarizations. It is shown that the second pulse can either be strongly amplified by taking up energy gained from the destruction of the exciton polarization or can be decreased drastically by giving up all its energy to excitons. Both the temporal and the spectral signatures of the transmitted pulse shapes agree well with model calculations.
