Self-Referenced Temperature Sensors Based on Cascaded Silicon Ring Resonator

This paper proposed a novel self-referenced thermometer based on a silicon cascaded micro-ring resonator (CMRR). A tapered waveguide cascades the reference ring covered by the titanium dioxide (TiO2) cladding with the sensing ring. Taking advantage of dual resonances derived from the two different waveguides, the simulation result shows the sensitivity of the CMRR is 63.4 pm/K utilizing the differential wavelength shifts (Delta lambda=lambda(sensing)-lambda(reference)) method. Moreover, the reference ring is temperature insensitive due to the thermo-optic effect of the silicon waveguide being offset out by the cladding with a negative thermo-optic coefficient (TOC). The work shows a new avenue for high-sensitivity and high-stability temperature sensing based on the silicon ring resonator.