Wavegiude Tapers and Waveguide Bends in AlGaAs-Based Two-Dimensional Photonic Crystals

We report experimental studies of the optical properties of two-dimensional low index-contrast AlGaAs-based photonic crystal waveguide structures. Transmission experiments were performed by use of the internal light source technique. Using photonic crystal waveguide tapers, high coupling efficiencies from ridge waveguides to photonic crystal waveguides are demonstrated. Enhanced bending efficiencies and increased band bandwidths are achieved by use of modified bends. Experimental transmission curves are compared with simulation results, and good agreement with calculated transmission curves is demonstrated. These results show the potential of photonic crystal structures in the fabrication of wavelength-scale integrated photonic devices.