We analyze the beam propagation in modulated waveguide arrays, which consist of two types of alternating waveguides with different widths. Using effective discrete equations, we identify the presence of the so-called Rowland ghost gap in the linear transmission spectrum, and consider the effect of Kerr-type nonlinear self-action, describing two distinct classes of discrete solitons: (ⅰ) conventional discrete solitons, and (ⅱ) discrete gap solitons. We demonstrate that the gap solitons can be efficiently generated by Gaussian input beams; both the soliton velocity and its propagation direction can be controlled by varying the input light intensity.
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