Generation of two-dimensional multicolored arrays and their weak beam control

Two-dimensional multicolored transverse arrays were demonstrated experimentally for the first time in a quadratic nonlinear medium. Cascaded noncollinear quadratic processes took place between input pulses and quadratic spatial solitons formed by spatial breakup of one of the pump beams with small ellipticity. Two-dimensional multicolored transverse arrays as well as transient grating were formed by cascaded noncollinear quadratic processes. Synchronously seeded supercontinuum pulses were diffracted and amplified, resulting in two-dimensional multicolored up-conversion parametric amplification. These two kinds of two-dimensional patterns were readily suppressed by seeding with weak second harmonic pulses in one of the pump pulses.