  The creation of electron-positron pairs by the strong-field Breit-Wheeler
process in intense short laser pulses is investigated in the framework of
laser-dressed quantum electrodynamics. Regarding laser field parameters in the
multiphoton regime, special attention is brought to the energy spectrum of the
created particles, which can be reproduced and explained by means of an
intuitive model. The model is based on the probabilities of multiphoton events
driven by the spectral components of the laser pulse. It allows, in particular,
to identify interferences between different pair production channels which
exhibit a characteristic dependence on the laser carrier-envelope phase.
