200-Ghz Spacing, 8ch, High-Speed Wavelength Selective Arrayed-Waveguide Grating Using Buried Plzt Waveguides

A wavelength selective AWG (arrayed-waveguide grating) was fabricated using buried PLZT ((Pb, La)(Zr, Ti)O-3) waveguides. It has 8 output channels with 200 GHz spacing. The buried PLZT waveguides have lower propagation loss and higher optical confinement compared to the previously reported ridge PLZT waveguides. Therefore, using buried PLZT waveguides, an AWG with shorter channel spacing than a conventional AWG can be designed and fabricated. The 3-dB bandwidth was 110 GHz, the maximum control voltage was 14 V, and the tuning range was 1600 GHz. Wavelength tuning was successfully demonstrated with a crosstalk of about -14 dB for TE (transverse electric) polarized light and -13 dB for TM (transverse magnetic) polarized light.