Ultrafast dynamics of carrier–LO phonon system in high electric field in polar semiconductors

The dynamics of carriers excited by an ultrashort laser pulse is simulated numerically in the presence of a strong electric field. The carrier density matrices (DMs) are treated within the equation of motion method by taking interaction with longitudinal optical (LO) phonons into account. It is shown that the temporal evolution of an electron DM exhibits a strong modification owing to LO phonon emissions in addition to interferences between the interband polarization and the optical pulse field in the external strong electric field.