  Optical devices based on photonic crystals such as waveguides, lenses and
beam-shapers, have received considerable theoretical and experimental attention
in recent years. The production of these devices has been facilitated by the
wide availability of silicon-on-insulator fabrication techniques. In this
theoretical work, we show the possibility to design a coherent PhC-based
beam-shaper. The basic photonic geometry used is a 2D square lattice of air
holes in a high-index dielectric core. We formulate the beam shaping problem in
terms of objective functions related to the amplitude and phase profile of the
generated beam. We then use a parallel tabu search algorithm to minimize the
two objectives simultaneously. Our results show that optimization of several
attributes in integrated photonics design is well within reach of current
algorithms.
