TE-Pass/TM-Stop On-Chip Mach-Zehnder interferometer with high phase sensitivity

Mach-Zehnder interferometer (MZI) has attracted intense research interest due to the extensive applications in optical integrated systems. This paper presents a TE-Pass/TM-Stop graphene-based on-chip MZI, including splitter, phase shift arm, reference arm and combiner. The splitter and combiner are based on subwavelength gratings (SWGs) coupler. Hybrid slot waveguides with photonic crystals (PhC) are adopted as the phase shift arm and the reference arm, with and without graphene, respectively. The results show that the phase sensitivity is 1010 rad/RIU-cm at 1.55 μm, which is 10 times higher than the strip waveguide-based graphene MZI.