Aluminium nitride on sapphire whispering gallery mode resonator data for photonic thermometry study

We have fabricated aluminium nitride on sapphire whispering gallery mode resonators with different coupling gaps between the radial resonator and the bus waveguides. Due to the moderate thermo-optic coefficient of our chosen material, the whispering gallery mode resonator exhibits temperature dependent resonance behaviour which we can exploit to create an integrated photonic thermometer with low temperature uncertainties. We present the characterisation results of our resonator along with temperature dependent measurements of its transmission spectrum.