학술논문

Integrated Electrical Properties of the Frequency Multiplexed Cryogenic Readout System for Polarbear/Simons Array
Document Type
Periodical
Source
IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. 31(5):1-5 Aug, 2021
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Detectors
Crosstalk
Resistance
Frequency division multiplexing
Physics
Inductance
SQUIDs
Superconducting resonators
microwave devices and components
superconducting electronics
multiplexing
instrumentation and readout of superconducting devices
superconducting detectors
millimeter
wave detectors
general detector topics
imaging arrays of detectors
satellites and large arrays
Language
ISSN
1051-8223
1558-2515
2378-7074
Abstract
Polarbear/Simons Array is a cosmic microwave background (CMB) polarization experiment, with science goals including a deep search for CMB B-mode polarization created by inflationary gravitational waves, and characterization of the CMB B-mode signal from gravitational lensing. When completed, Simons Array will have over 20,000 superconducting transition-edge sensor bolometers, cooled to 300 mK with closed-cycle cryogenics. This significant increase in detectors and sensitivity is enabled by advancements in frequency multiplexed readout. The detectors are read out with DfMux digital frequency-domain multiplexing, with 40 channels read out by each SQUID array, with frequency channels between 1 and 5 MHz defined by an inductor and capacitor in series with each detector. After the system was completed and characterized for Polarbear-2a, modifications were made that further improved performance for Polarbear-2b. We present the characterization of the integrated cryogenic readout system for Polarbear-2a and Polarbear-2b, and comparison of properties including stray impedance and frequency scatter.