Radiation Effects in Optical Materials and Photonic Devices

The chapter continues previous reviews on radiation effects in optical fibers and on the use of optical fibers/optical fiber sensors in radiation monitoring, published by InTech in 2010 and 2012, by referring to radiation effects in optical materials, with an emphasis on those operating from visible to mid-IR, and on some photonic devices such as optical fibers for amplifiers, fiber Bragg gratings and long period gratings. The focus is on optical materials and fiber-based devices designed for both terrestrial and spaceborne applications. For the presented subjects, an overview of available data on X-rays or gamma rays, electron beams, alpha particles, neutrons, and protons effects is provided. In addition, comments on dose rate, dose, and/or temperature effects on materials and devices degradation under irradiation are mentioned, where appropriate. The optical materials and photonic devices reliability under ionizing radiation exposure is discussed as well, as the opportunities to use them in developing radiation sensors or dosimeters. The chapter includes an extensive bibliography and references to last published results in the field. Novel proposed applications of photonic devices in charged particle beam diagnostics, quasi-distributed radiation field mapping and the evaluation of radiation effects in materials for mid-IR spectroscopy are briefly introduced to the reader

Optical fibers and optical fiber sensors used in radiation monitoring

peer-reviewedBy their very nature, optical fibers and, by extension, intrinsic and extrinsic optical fiberbased sensors are promising devices to be used in very different and complex environments considering their characteristics such as: capabilities to work under strong electromagnetic fields; possibility to carry multiplexed signals (time, wavelength multiplexing); small size and low mass; ability to handle multi-parameter measurements in distributed configuration; possibility to monitor sites far away from the controller; their availability to be incorporated into the monitored structure; wide bandwidth for communication applications. In the case of the optical fibers, the possibility to be incorporated into various types of sensors and actuators, free of additional hazards (i.e. fire, explosion), made them promising candidates to operate in special or adverse conditions as those required by space or terrestrial applications (spacecraft on board instrumentation, nuclear facilities, future fusion installations, medical treatment and diagnostics premises, medical equipment sterilization). Major advantages to be considered in using optical fibers/optical fiber sensors for radiation detection and monitoring refer to: real-time interrogation capabilities, possibility to design spatially resolved solutions (the capability to build array detectors), in-vivo investigations (i.e. inside the body measurements).PUBLISHEDpeer-reviewe

Chapter Optical fibers and optical fiber sensors used in radiation monitoring

Communications engineering / telecommunication

Chapter Optical fibers and optical fiber sensors used in radiation monitoring

Communications engineering / telecommunication

Impact of 3MeV Energy Proton Particles on Mid-IR QCLs

This paper reports the results obtained for a distributed-feedback quantum cascade laser (DFB-QCL) exposed to different fluences of proton particles: 1014, 1015 and 1016 p/cm2. Dedicated laboratory setups were developed to assess the irradiation-induced changes in this device. Multiple parameters defining the QCL performances were investigated prior to and following each irradiation step: (i) voltage-driving current; (ii) emitted optical power-driving current; (iii) central emitting wavelength-driving current; (iv) emitted spectrum-driving current; (v) transversal mode structure-driving current, maintaining the system operating temperature at 20 °C. The QCL system presented, before irradiation, two emission peaks: a central emission peak and a side peak. After proton irradiation, the QCL presented a spectral shift, and the ratio between the two peaks also changed. Even though, after irradiation, the tunning spectral range was reduced, at the end of the tests, the system was still functional

Impact of 3MeV Energy Proton Particles on Mid-IR QCLs

This paper reports the results obtained for a distributed-feedback quantum cascade laser (DFB-QCL) exposed to different fluences of proton particles: 1014, 1015 and 1016 p/cm2. Dedicated laboratory setups were developed to assess the irradiation-induced changes in this device. Multiple parameters defining the QCL performances were investigated prior to and following each irradiation step: (i) voltage-driving current; (ii) emitted optical power-driving current; (iii) central emitting wavelength-driving current; (iv) emitted spectrum-driving current; (v) transversal mode structure-driving current, maintaining the system operating temperature at 20 °C. The QCL system presented, before irradiation, two emission peaks: a central emission peak and a side peak. After proton irradiation, the QCL presented a spectral shift, and the ratio between the two peaks also changed. Even though, after irradiation, the tunning spectral range was reduced, at the end of the tests, the system was still functional

Optical fibers and optical fiber sensors used in radiation monitoring

By their very nature, optical fibers and, by extension, intrinsic and extrinsic optical fiberbased sensors are promising devices to be used in very different and complex environments considering their characteristics such as: capabilities to work under strong electromagnetic fields; possibility to carry multiplexed signals (time, wavelength multiplexing); small size and low mass; ability to handle multi-parameter measurements in distributed configuration; possibility to monitor sites far away from the controller; their availability to be incorporated into the monitored structure; wide bandwidth for communication applications. In the case of the optical fibers, the possibility to be incorporated into various types of sensors and actuators, free of additional hazards (i.e. fire, explosion), made them promising candidates to operate in special or adverse conditions as those required by space or terrestrial applications (spacecraft on board instrumentation, nuclear facilities, future fusion installations, medical treatment and diagnostics premises, medical equipment sterilization). Major advantages to be considered in using optical fibers/optical fiber sensors for radiation detection and monitoring refer to: real-time interrogation capabilities, possibility to design spatially resolved solutions (the capability to build array detectors), in-vivo investigations (i.e. inside the body measurements)