Development and optimization of integrated photonic waveguide and passive devices on silicon on lithium niobate material platform towards creation of phase modulator

The numerical design procedure for the special type of waveguide, its parameters, and based on this waveguide directional and MMI coupler is discussed. We focus on the waveguide dimensions optimization for the phase modulator which appeared to be
${90\mathrm{x}900}$
nm for efficient modulation. The minimum bending radius, minimal distances between waveguides, and directional and MMI -coupler topology were obtained.