Estimation of waveguide phase error in silica-based waveguides

A new estimation method is proposed in order to clarify waveguide phase error factors. Using the proposed method, it is possible to analyze such factors as core size error and refractive index error, which cause optical phase error in waveguides. This method is applied to silica-based waveguides to estimate the waveguide phase error. This revealed an average core size error of 2.1×10^-3 μm and an average refractive index error of 1.9×10^-6. Finally, based on the measured phase error values, the optimum arrayed-waveguide grating (AWG) configuration is considered with a view to achieving low crosstalk