Brillouin-zone spectroscopy of photonic lattices

Optics can be used to understand wave dynamics in periodic systems, including the technologically important photonic crystals, photonic crystal fibers, and waveguide arrays. A single shot technique for Brillouin zone spectroscopy of photonic lattices, relying on partially incoherent input and Fourier imaging of the output, was analyzed. The techniques directly maps the boundaries of the Brillouin zones, the regions of normal and anomalous diffraction within them, and the power spectra of modes guided by embedded defects. It was observed that when the photonic lattice is nonlinear, it is possible to mark the areas of normal and anomalous dispersions with in every Brillouin zone.