Optical Multi-ring Cascade Cavity Temperature Sensor with Ultra-High Sensitivity

An ultra-small integrated photonic ten-order resonators temperature sensor has been proposed and demonstrated and fabrication using well-developed MEMS technologies incorporates a silicon ring resonator. The temperature variation is measured by monitoring the shift in the ten-order resonant wavelength of the silicon resonator, which was induced by the thermo-optic effect and the thermal expansion effect. The best achieved sensitivity is about 130 pm/°C for a waveguide width of 450 nm, and the radius of the micro ring is about 5 μm. Meanwhile, the two-channel sensor based on double racetrack rings is also reported.