Regensburg 2019 – wissenschaftliches Programm
HL 18.5: Hauptvortrag
Dienstag, 2. April 2019, 11:10–11:40, PHY 5.0.20
Development of Kinetic Inductance Detectors for polarimetric applications in plasma diagnostics — •Francesco Mazzocchi1, Eduard Driessen2, Shibo Shu2, Giovanni Grossetti1, Dirk Strauss1, and Theo Scherer1 — 1Karlsruhe Institute of Technology, Eggenstein Loepoldshafen, Germany — 2Institute de RadioAstronomie Millimetrique, Grenoble, France
Polarimetry is a technique that measures the Faraday rotation in a magnetized medium, such as a fusion plasma. It allows to determine various fundamental plasma parameters, such as current density when used independently from other diagnostics and like poloidal field and electron density when coupled to specific systems (i.e. interferometry). To mitigate these issues of current systems, we have considered to use in our device a Quantum Cascade Laser (QCL). The lack of power of such source requires the use of extremely sensitive detectors, hence the development of custom superconducting Kinetic Inductance Detector (KID) presented in this work. The whole system will be composed of a cryostat containing the source and the detector (both of which require cryogenic temperatures to operate optimally) and a beam delivery system, consisting of suitable waveguides and a diamond window on the reactor side, to have a very strong pressure barrier between the tritium rich atmosphere of the fusion reactor and the vacuum of the polarimeter side waveguides. The dielectric and mechanical properties of the synthetic diamond allow us to have such barrier without compromising the beam transmission factor.