A silicon racetrack resonator modulator, based on phase-match control, is proposed. The device is comprised of a straight
waveguide evanescently coupled to a ring resonator in the shape of a racetrack. A PN junction, formed in the straight
waveguide, is used to control the degree of phase-match in the coupler. Consequently, the coupling, and hence the power
transmission, is controlled by the voltage across the PN junction. The predicted free spectral range and switching voltage are,
respectively, 0.4 nm and 7.5 Volt, while the device dimensions are approximately 0.7 mm by 0.15 mm. The device behavior
is analyzed using two different analytic approaches for the coupling, the results of which are compared to numerical
A tunable ring resonator (RR) formed from Si/SiO2 waveguides with an electro-optic polymer cladding is proposed with emphasis on the trade-off between the tuning voltage and ring radius. The ring resonator circuit combines the advantages of Si/SiO2 and polymer technologies. The advantages of this hybrid ring design over previously proposed tunable silicon rings include an increased switching speed, from 5 GHz to 20 to 100 GHz, single-polarity instead of dual-polarity voltage tuning and a voltage-independent quality factor. The hybrid design also displays a greater free spectral range (1.85 nm instead of 0.1 nm) and a wider tuning range (0.925 nm instead of 0.05 nm) and is further compatible with silicon devices. Moreover, the device has a high quality factor of 3.4×104.
We design a high-speed tunable electro-optical (EO) polymer-clad silicon over insulator (SOI) racetrack resonator with a 80-µm length and 5-µm radius that exhibits a switching speed of 100 GHz, a tuning voltage of 6.81 V, and an extinction ratio of 109.55 dB. This work employs high electro-optical coefficient polymers (r33=1000 pm/V), which are currently under development, to implement very high speed switches.
A single-mode waveguide is fabricated using ion exchange in a molten bath of KNO3 salt. The mode effective index is measured using a mode-lines (M-lines) experiment. The waveguide is then etched, and the M-lines experiment is performed again. The two measurements are sufficient for refractive index profile (RIP) reconstruction, which is assumed to be Gaussian. The reconstructed profile is checked using a numerical technique and is then compared to the inverse technique, showing the inverse technique limitations.