Characterizing 1550 nm optical components down to 8 K

Cryogenics, vol. 142, pp. 103895

Abstract

Thermal noise sources are relevant for future gravitational wave detectors due to the foreseen increase in sensitivity, especially at frequencies below . As most thermal noise sources scale with the square root of the temperature, cooling critical optical components and their suspension system is essential. This also requires a much wider range of temperature compatibility from all technology deployed in the last suspension stages, including displacement and inertial sensors. We demonstrate and characterize a setup for stable light sources and light intensity sensing for temperatures from 300 to . Commercial collimators and fibers were tested to use light from stabilized laser sources in the cryogenic environment. We also investigated multiple semiconductor compositions of photodiodes and identified a solution with high and stable responsivity at .

Authors 7

1. Tim J. Kuhlbusch corresponding Aachen III. Physikalisches Institut

   RWTH Aachen University

   Affiliation as printed

   III. Physikalisches Institut, RWTH Aachen University, Otto-Blumenthal-Straße, 52074, Aachen, Germany

2. M Zeoli

   University of Liège · UCLouvain

   Affiliation as printed

   Centre for Cosmology, Particle Physics and Phenomenology (CP3), UCLouvain, Chemin du Cyclotron 2, B-1348, Louvain-la-Neuve, Belgium

   Precision Mechatronics Laboratory, ULiège, B52/Quartier Polytec 1, B-4000, Liège, Belgium

3. Robert Joppe Aachen III. Physikalisches Institut

   RWTH Aachen University

   Affiliation as printed

   III. Physikalisches Institut, RWTH Aachen University, Otto-Blumenthal-Straße, 52074, Aachen, Germany

4. Christophe Collette

   University of Liège

   Affiliation as printed

   Precision Mechatronics Laboratory, ULiège, B52/Quartier Polytec 1, B-4000, Liège, Belgium

5. Thomas Hebbeker Aachen III. Physikalisches Institut

   RWTH Aachen University

   Affiliation as printed

   III. Physikalisches Institut, RWTH Aachen University, Otto-Blumenthal-Straße, 52074, Aachen, Germany

6. Joris V. van Heijningen

   National Institute for Subatomic Physics · Vrije Universiteit Amsterdam · UCLouvain

   Affiliation as printed

   Centre for Cosmology, Particle Physics and Phenomenology (CP3), UCLouvain, Chemin du Cyclotron 2, B-1348, Louvain-la-Neuve, Belgium

   Department of Physics and Astronomy, VU Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands

   Nikhef, Science Park 105, 1098 XG Amsterdam, the Netherlands

7. A. Stahl Aachen III. Physikalisches Institut

   RWTH Aachen University

   Affiliation as printed

   III. Physikalisches Institut, RWTH Aachen University, Otto-Blumenthal-Straße, 52074, Aachen, Germany