Superconducting Coplanar Switch and Phase Shifter for CMB Applications

• Published in: Journal of low temperature physics 2016-08, Vol.184 (3-4), p.547-552
• Main Authors: Bordier, G., Cammilleri, V. D., Belier, B., Bleurvacq, N., Gadot, F., Ghribi, A., Piat, M., Tartari, A., Zanonni, M.
• Format: Article
• Language: English
• Subjects: Astrophysics; Characterization and Evaluation of Materials; Condensed Matter Physics; Magnetic Materials; Magnetism; Physics; Physics and Astronomy
• ISSN: 0022-2291; 1573-7357
• DOI: 10.1007/s10909-016-1567-z

The next generations of cosmic microwave background (CMB) instruments will be dedicated to the detection and characterization of CMB B-modes. To measure this tiny signal, instruments need to control and minimize systematics. Signal modulation is one way to achieve such a control. A new generation of focal planes will include the entire detection chain. In this context, we present a superconducting coplanar switch driven by DC current. It consists of a superconducting microbridge which commutes between its on (superconducting) and off (normal metal) states, depending on the amplitude of the injected current compared to the critical current. If the current injected inside the bridge is lower than the critical current, the phase of the signal passing through the bridge is tunable. A first prototype of this component working as a switch and as a phase shifter at 10 GHz has been made. The principle, the setup, and the first measurements made at 4 K will be shown.