Hi Sanaz,
There are examples for each type of Mach-zehnder -based component. LiNb Mack-Zehnder modulators has two electrical modulating signals. while Mch-Zehnder modulator has only one electrical modulating signal. Another component called Mach-Zehnder interferometer does not have any electrical input signals. Only it simulates the interference between the optical signals.
you can find a detailed description of the model used with each component and the setting parameters for each in its manual.
Hope that helps to start your project.
Let us know if you have any other concern.
thanks
Mohamed Abouseif