Abstract
We demonstrate a dual-material integrated photonic thermometer, fabricated by high accuracy micro-transfer printing. A freestanding diamond micro-disk resonator is printed in close proximity to a gallium nitride on a sapphire racetrack resonator, and respective loaded Q factors of 9.1 × 104 and 2.9 × 104 are measured. We show that by using two independent wide-bandgap materials, tracking the thermally induced shifts in multiple resonances, and using optimized curve fitting tools the measurement error can be reduced to 9.2 mK. Finally, for the GaN, in a continuous acquisition measurement we record an improvement in minimum Allan variance, occurring at an averaging time four times greater than a comparative silicon device, indicating better performance over longer time scales.
Highlights
Photonic integrated circuits (PICs) are increasingly being implemented in a variety of sensing and metrology applications [1,2], with the often cited benefits being the reduction in size and cost because of the small form factor of photonic devices, as well as improvements in stability, robustness, and often sensitivity
We demonstrate a dual-material integrated photonic thermometer, fabricated by high accuracy micro-transfer printing
We show that by using two independent wide-bandgap materials, tracking the thermally induced shifts in multiple resonances, and using optimized curve fitting tools the measurement error can be reduced to 9.2 mK
Summary
Photonic integrated circuits (PICs) are increasingly being implemented in a variety of sensing and metrology applications [1,2], with the often cited benefits being the reduction in size and cost because of the small form factor of photonic devices, as well as improvements in stability, robustness, and often sensitivity. There has been much work in developing photonic thermometers which are more robust to mechanical degradation and electromagnetic interference, with recent work utilizing silicon resonators (both microrings [3,5] and photonic crystal cavities [4]) which have high thermal sensitivities afforded by silicon’s large thermo-optic coefficient. They are more susceptible to long-term drift and absorption based self-heating [4], both due to two-photon absorption and surface state absorption [13], leading to inaccurate readings over longer time scales. Other methods to increase the number of peaks available for this form of multi-peak tracking include using devices with smaller free spectral ranges, or using cascaded resonators in a single material
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
