I have following doubts:
1) What is the state of the art technology to realize Mach-Zehnder modulator? Is it to realize it on thin-film lithium niobate? If yes, then why not many commercial companies are manufacturing on these instead of Ti diffusion bulk LN based?
2) Does thin film LN based modulator require Ti diffusion?
3) I want to start designing MZM using Lumerical. I tried to find search online but couldn't find good sources. If you can provide some references, it'll be very helpful.