Fig. 1. (a) Schematic hybrid Si₃N₄ asymmetric MZI with EO polymer cladding (not to scale). (b) Chemical structure of dipolar chromophore YLD124. (c) Cross section of hybrid EO phase shifter in MZI (w = 2 µm, h = 300 nm). (d) Optical field distribution of the hybrid phase shifter with the evanescent field intensity (Γ_opt) of 30% in the EOP cladding. (e) Electric field distribution of the phase shifter for poling and zoomed-in interfacial electric field distribution. (d = 6 µm, electric field = 50 V/µm).

Fig. 2. Illustration of conventional electric field poling from (a) V = 0 (before poling) to (b) V++ (strong electric field), and (c) segmented electric field poling from V = 0 to V+ (weak electric field) and then V++ (strong electric field). Electrode gap d = 6 µm.

Fig. 3. (a)–(c) Scanning electron microscope (SEM) images of Si₃N₄ waveguide and coplanar GSG electrodes. (d) Illustration of the waveguide and electrodes after coating the EOP cladding and the electron dispersive spectra of Al (e) and carbon (f) in the EOP film.

Fig. 4. EO tuning of AMZI-1 after (a), (c) Step-1 poling and (b), (d) Step-2 poling.

Fig. 5. EO tuning of AMZI-5 with an electrode length of 10 mm.

Fig. 6. EO tuning of AMZI-6 with an electrode length of 5 mm after (a) Step-1 poling and (b) Step-2 poling.