Hello Fabrice,
Yes, it is possible.
Have a look at the OptiBPM Technical Background and Tutorials, pparticularly Lesson 11, Integrated optical circuit simulation using OptiBPM and OptiSystem – Scattering data export. There you will see a Mach-Zehnder interferometer modelled in OptiSystem. part of the optical system (the waveguide coupling ) was modelled with OptiBPM, and the results ttansferred to OptiSystem by means of a transfer matrix. Maybe this example will help you get started with your problem? Regards, Steve