Novel multi-splitting widely tunable filter on SOI technology

This paper proposes and makes numerical investigation of new tunable optical filter which utilized multiple coupled silicon wire waveguides on SOI structures. Numerical simulation by 2D FDTD proves its general conception and demonstrates that a short 321 μm structure with 32 couplers has spectral resolutions 1.7 nm, loss -1 dB and side-lobes below -26 dB. It provides wavelength tuning (without Vernier principle) within total FSR 36.8 nm at central optical wavelength 1.55 μm by temperature change up to 100 C° in four sets of thermo optic phase shifters. Device of 1 cm size provides 0.05 nm filter linewidth. Filter can be manufactured by CMOS compatible technology and very promising for applications in photonics.