Modeling the propagation of ultrafast optical pulses in a semiconductor mirror and microcavities

Abstract

Fourier methods are used to model the propagation of ultrashort pulses of light through GaAs/AlGaAs microcavities. Resonance effects are seen in the time dependence of field amplitude in the cavity, with the electric-field amplitude in the cavity center increasing in a similar time to the pulse duration but then decaying at a much slower rate, with a longer decay time for more reflective distributed Bragg mirrors, in agreement with experimental measurements. Two separate sets of novel transient peaks are quantitatively studied. Pulses longer than 100 fs produce peaks with decreasing period for increased detuning between pulse wavelength and cavity length. Shorter pulses with spectral content broader than the range of wavelengths for which the mirrors are highly reflective show transient peaks with period independent of detuning. These peaks could affect a wide range of experiments using ultrafast pulses to study microcavities.