The role of leaking modes on dynamic range of amplitude and phase electro-optic light modulators

This research discusses the leaking modes as an important optical noise factor, that limits dynamic range and contrast in the electro-optic modulators. The simulation demonstrates that the power of leaking modes at the output port of a common Mach-Zehnder modulator consists a 10-15% of the main waveguide mode even for the open state. When it is closed the leaking modes power increases due to the energy conservation law, so even after a Fresnel reflection from the modulator crystal's border the crosstalk can reach about 0,1-1% of the input power.