Photon trajectories in multiple slit interference experiments with femtosecond pulses of light?

A burst of pulses was observed at each output of the experimental arrangement, when a multiple slit was illuminated with a femtosecond pulse of light. Multiple times of fly became observably different and thus, each pulse in an output burst could be univocally associated with a particular slit. Nevertheless, interference between non-overlapping pulses was also observed. Previously, we have used a Fourier Optics approach to explain why interference was observed in conditions where which-path information was available [1]. We show in this work that the observed interference pattern can also be successfully described assuming that the energy of the light travels following well defined paths. Ref.: [1] ``Ultra fast response of arrayed waveguide gratings,'' L. Grave de Peralta, A.A. Bernussi and H. Temkin, IEEE Journal of Quantum Electronics, vol. 43, 473 (2007).