In this letter, we propose a new approach of
hetero-cladding for realization of compact CMOS compatible silicon photonic
directional couplers. The proposed hetero-cladding comprises ferroelectric
BaTiO<sub>3</sub> (BTO) and SiO<sub>2</sub> to control the evanescent mode
within the structure. The results show very small and identical coupling length
for both TE and TM modes with reduced device cross-section, which promises for
a huge reduction in the footprint of both conventional and programmable
photonic integrated circuits. The concept can also be utilized to design
compact, low loss and energy efficient phase shifters, other types of couplers,
sensors etc.
Low-loss and energy efficient modulation in silicon photonic waveguides by adiabatic elimination scheme