Integrated photonics is poised to become a mainstream solution for high-speed data communications and sensing in harsh radiation environments,such as outer space,high-energy physics facilities,nuclear power plants,and...Integrated photonics is poised to become a mainstream solution for high-speed data communications and sensing in harsh radiation environments,such as outer space,high-energy physics facilities,nuclear power plants,and test fusion reactors.Understanding the impact of radiation damage in optical materials and devices is thus a prerequisite to building radiation-hard photonic systems for these applications.In this paper,we report real-time,in situ analysis of radiation damage in integrated photonic devices.The devices,integrated with an optical fiber array package and a baseline-correction temperature sensor,can be remotely interrogated while exposed to ionizing radiation over a long period without compromising their structural and optical integrity.We also introduce a method to deconvolve the radiation damage responses from different constituent materials in a device.The approach was implemented to quantify gamma radiation damage and post-radiation relaxation behavior of SiO2-cladded SiC photonic devices.Our findings suggest that densification induced by Compton scattering displacement defects is the primary mechanism for the observed index change in SiC.Additionally,post-radiation relaxation in amorphous SiC does not restore the original pre-irradiated structural state of the material.Our results further point to the potential of realizing radiation-hard photonic device designs taking advantage of the opposite signs of radiation-induced index changes in SiC and SiO2.展开更多
文摘Integrated photonics is poised to become a mainstream solution for high-speed data communications and sensing in harsh radiation environments,such as outer space,high-energy physics facilities,nuclear power plants,and test fusion reactors.Understanding the impact of radiation damage in optical materials and devices is thus a prerequisite to building radiation-hard photonic systems for these applications.In this paper,we report real-time,in situ analysis of radiation damage in integrated photonic devices.The devices,integrated with an optical fiber array package and a baseline-correction temperature sensor,can be remotely interrogated while exposed to ionizing radiation over a long period without compromising their structural and optical integrity.We also introduce a method to deconvolve the radiation damage responses from different constituent materials in a device.The approach was implemented to quantify gamma radiation damage and post-radiation relaxation behavior of SiO2-cladded SiC photonic devices.Our findings suggest that densification induced by Compton scattering displacement defects is the primary mechanism for the observed index change in SiC.Additionally,post-radiation relaxation in amorphous SiC does not restore the original pre-irradiated structural state of the material.Our results further point to the potential of realizing radiation-hard photonic device designs taking advantage of the opposite signs of radiation-induced index changes in SiC and SiO2.