Discrete solitons, self-localized states which can exist in both one- and two-dimensional nonlinear photonic lattices, have attracted a lot of attention over the recent years [1]. The interplay between the underlying periodicity and nonlinear self-action enables a whole lot of new opportunities for all-optical control, which are not possible in homogeneous media [1]. Of particular interest are pulses which are localized both in space and in time as a result of balance between the focusing nonlinearity, diffraction, and anomalous dispersion. However such optical bullets [2] are inherently multi-dimensional, and that is why they are always unstable in Kerr media. Discreteness in photonic lattices can provide an additional stabilization mechanism, and indeed stable continuous-discrete solitons were found to be possible in nonlinear waveguide arrays [3]. However, these discrete light bullets are strongly trapped in a few waveguide channels, and hence their mobility is practically reduced to the longitudinal dimension, whereas they cannot move across the photonic lattice.
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