TY - JOUR

T1 - Fiber backscatter under increasing exposure to ionizing radiation

AU - Rohr, Johann Max

AU - Ast, Stefan

AU - Gerberding, Oliver

AU - Reiche, Jens

AU - Heinzel, Gerhard

N1 - Funding Information: We gratefully acknowledge support by the European Space Agency (ESA) within the project "Phase Reference Distribution System" (8586/16/NL/BW) and the Deutsches Zentrum für Luft-und Raumfahrt (DLR) with funding from the Bundesministerium für Wirtschaft und Technologie (Project Ref. Number 50 OQ 1801, based on work done under Project Ref. Number 50 OQ 1301 and 50 OQ 0601). Furthermore, the authors gratefully acknowledge support by Jochen Kuhnhenn and Simone Schmitz from the Fraunhofer Institute for Technological Trend Analysis (INT), Euskirchen, Germany in operating the radiation facilities. The authors also would like to thank the current and former members of the "Backlink Team" for numerous useful discussions.

PY - 2020/11/9

Y1 - 2020/11/9

N2 - The Laser Interferometer Space Antenna (LISA) will measure gravitational waves by utilizing inter-satellite laser links between three triangularly-arranged spacecraft in heliocentric orbits. Each spacecraft will house two separate optical benches and needs to establish a phase reference between the two optical benches which requires a bidirectional optical connection, e.g. a fiber connection. The sensitivity of the reference interferometers, and thus of the gravitational wave measurement, could be hampered by backscattering of laser light within optical fibers. It is not yet clear if the backscatter within the fibers will remain constant during the mission duration, or if it will increase due to ionizing radiation in the space environment. Here we report the results of tests on two different fiber types under increasing intensities of ionizing radiation: SM98-PS-U40D by Fujikura, a polarization maintaining fiber, and HB1060Z by Fibercore, a polarizing fiber. We found that both types react differently to the ionizing radiation: The polarization maintaining fibers show a backscatter of about 7 ppm·m−1 which remains constant over increasing exposure. The polarizing fibers show about three times as much backscatter, which also remains constant over increasing exposure. However, the polarizing fibers show a significant degradation in transmission, which is reduced to about one third.

AB - The Laser Interferometer Space Antenna (LISA) will measure gravitational waves by utilizing inter-satellite laser links between three triangularly-arranged spacecraft in heliocentric orbits. Each spacecraft will house two separate optical benches and needs to establish a phase reference between the two optical benches which requires a bidirectional optical connection, e.g. a fiber connection. The sensitivity of the reference interferometers, and thus of the gravitational wave measurement, could be hampered by backscattering of laser light within optical fibers. It is not yet clear if the backscatter within the fibers will remain constant during the mission duration, or if it will increase due to ionizing radiation in the space environment. Here we report the results of tests on two different fiber types under increasing intensities of ionizing radiation: SM98-PS-U40D by Fujikura, a polarization maintaining fiber, and HB1060Z by Fibercore, a polarizing fiber. We found that both types react differently to the ionizing radiation: The polarization maintaining fibers show a backscatter of about 7 ppm·m−1 which remains constant over increasing exposure. The polarizing fibers show about three times as much backscatter, which also remains constant over increasing exposure. However, the polarizing fibers show a significant degradation in transmission, which is reduced to about one third.

UR - http://www.scopus.com/inward/record.url?scp=85096031438&partnerID=8YFLogxK

U2 - 10.1364/OE.404139

DO - 10.1364/OE.404139

M3 - Article

C2 - 33182947

AN - SCOPUS:85096031438

VL - 28

SP - 34894

EP - 34903

JO - Optics Express

JF - Optics Express

SN - 1094-4087

IS - 23

ER -