Fiber-Optic Silicon Fabry-Perot Interferometric Bolometer: The Influence of Mechanical Vibration and Magnetic Field

Journal Article · 20 January 2020 · Journal of Lightwave Technology

DOI: https://doi.org/10.1109/JLT.2020.2968538 · OSTI ID:1593359

Sheng, Qiwen  ^[1]; Liu, Guigen ^[2]; Uddin, Nezam  ^[2]; Reinke, Matthew L.  ^[3]; Han, Ming  ^[2]

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1. Michigan State Univ., East Lansing, MI (United States). Dept. of Electrical and Computer Engineering; Michigan State University
2. Michigan State Univ., East Lansing, MI (United States). Dept. of Electrical and Computer Engineering
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Plasma radiation plays an important role in the operation and control of magnetic confinement fusion and is typically measured by bolometers. Here, we study the influence of mechanical vibration and magnetic field, which are typically present in magnetic confinement fusion devices, on the performance of a fiber-optic bolometer (FOB) based on silicon Fabry-Perot interferometer (FPI) demodulated by a scanning diode laser. It is found that both the vibration and magnetic field could cause large noise due to the birefringence of the silicon FPI. To mitigate the birefringence effects, we demonstrated two effective methods: polarization maintaining FOB and polarization scrambling. We show that two methods can be effective in mitigating the effect caused by the sensor birefringence: (1) replacing the regular single-mode fiber in the FOB system with polarization-maintaining fiber and (2) using a polarization scrambler after the laser source. For both methods, no significant increase in the noise was observed in the vibration and magnetic field tests. Finally, our research highlights the importance of the polarization management for the FOB systems toward their practical applications in magnetic-confinement fusion systems.

• Research Organization: Michigan State Univ., East Lansing, MI (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES)
• Grant/Contract Number: AC05-00OR22725; SC0019058
• OSTI ID: 1593359
• Journal Information: Journal of Lightwave Technology, Journal Name: Journal of Lightwave Technology Journal Issue: 8 Vol. 38; ISSN 0733-8724
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English