Design of a photonic bolometric sensor using microring resonators for high-energy radiation detection.

Monitoring various types of space radiation is critical in space missions, as such radiation cannot be effectively detected from ground-based stations. Picosatellites and CubeSats are increasingly used for space research, including the measurement of gamma radiation from terrestrial gamma-ray flashes and gamma-ray bursts, whereas these platforms are limited in payload capacity. In this paper, we propose and theoretically demonstrate a novel integrable photonic structure for space radiation detection, working based on resonance shifts in micro-ring resonators induced by thermal energy deposition. The device is predicted to detect energy depositions exceeding ~ 50 keV, limited by predicted thermal noise equivalent power (NEPth), with a sensitivity of 1.52 fm/MeV at 100 MeV deposited energy. Using the intensity interrogation method employing a 16-bit analog-to-digital converter, a resolution of 74.7 keV could be achieved. Among various candidate materials evaluated for the absorbing layer, gold was selected due to its high efficiency and compatibility with standard photonic fabrication processes. The proposed sensor can exhibit an absorption efficiency ranging from over 1% to nearly 100% for gamma-ray photons in the 10–270 keV range. The same design can also be adapted for detecting high-energy electrons, and, with suitable modifications in the absorption mechanism, may be extended to other types of space radiation. Integrating such compact and lightweight sensors can significantly enhance the detection capabilities of smart satellites in monitoring diverse radiation sources in space, and theoretical studies of the proposed design demonstrate its potential for future implementation in practical space applications.