I also want to add that External modulators offer a way to reduce or eliminate chirp because the laser source is held in the narrow linewidth, steady-state mode. External modulator is typically either a LiNbO3 modulator or an electroabsorptive modulator. In this lesson the chirp induced by the LiNbO3 is analyzed based on the voltage of operation.The modulator is operating in the quadrature mode. This means that the bias voltage places the modulator at the midpoint of the optical response curve, and therefore, the intensity is at half of its peak value. The parameters utilized to setup the modulator. The extinction ratio is set to 200dB to avoid any chirp caused by asymmetric Y-branch waveguide. The modulator is set to work in a non-normalized way, which means the electrical input signal will not be normalized.
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