Development of Microwave Kinetic Inductance Detector for Cosmological Observations

Abstract

SUMMARY A precise measurement of Cosmic Microwave Background (CMB) provides us rich information about the universe. In particular, its asymmetric polarization patterns, B-modes, are smoking gun signature of inflationary universe. Magnitude of the B-modes is order of 10 nK. Its measurement requires a high sensitive millimeter-wave telescope with a large number of superconducting detectors on its focal plane. Microwave Kinetic Inductance Detector (MKID) is appropriate detector for this purpose. MKID camera has been developed in cooperation of National Astronomical Observatory of Japan (NAOJ), Institute of Physical and Chemical Research (RIKEN), High Energy Accelerator Research Organization (KEK), and Okayama University. Our developments of MKID include: fabrication of high-quality superconducting film; optical components for a camera use; and readout electronics. For performance evaluation of total integrated system of our MKID camera, a calibration system was also developed. The system was incorporated in a 0.1 K dilution refrigerator with modulated polarization source. These developed technologies are applicable to other types of detectors.

GroundBIRD: Observing Cosmic Microwave Polarization at Large Angular Scale with Kinetic Inductance Detectors and High-Speed Rotating Telescope

“…Values of the design parameters are listed in Table 2. The noise equivalent temperatures (NET) for the CMB are the expected values from the laboratory measurements, i.e., the CMB polarization emulator [10,11]. A MKID readout system with direct down conversion method is being developed [12].…”