  We report on a simple and compact experimental scheme to generate high power,
ultrafast, higher order vortex array beams. Simply by using a dielectric
microlens array (MLA) and a plano-convex lens we have generated array beams
carrying the spatial property of the input beam. Considering the MLA as a 2D
sinusoidal phase grating, we have numerically calculated the intensity pattern
of the array beams in close agreement with the experimental results. Using
Gaussian embedded vortex beams of order as high as l= 6, we have generated
vortex array beams with individual vortices of order as high as l= 6. We have
also theoretically derived the parameters controlling the intensity pattern,
size and the pitch of the array and verified experimentally. The single-pass
frequency-doubling of the vortex array at 1064 nm in a 1.2 mm long BiBO crystal
produced green vortex array of order, l_sh= 12, twice the order of the pump
beam. Using lenses of different focal lengths, we have observed the vortex
array of all orders to follow the focusing dependent conversion similar to the
Gaussian beam. The maximum power of the green vortex array is measured to be
138 mW at a single-pass efficiency as high as ~3.65%. This generic experimental
scheme can be used to generate array beams of desired spatial intensity profile
across wide wavelength range by simply changing the spatial profile of the
input beam.
