Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Low-Temperature Detectors for CMB Imaging Arrays



Johannes Hubmayr, Jason E. Austermann, James A. Beall, Daniel T. Becker, Bradley J. Dober, Shannon M. Duff, Jiansong Gao, Gene C. Hilton, Christopher M. McKenney, Joel N. Ullom, Jeffrey L. Van Lanen, Michael R. Vissers


We review advances in low-temperature detector (LTD) arrays for cosmic microwave background (CMB) polarization experiments, with a particular emphasis on imaging arrays. We briefly motivate the science case, which has spurred a large number of independent experimental efforts. We describe the challenges associated with CMB polarization measurements, and how these challenges impact LTD design. Key aspects of an ideal CMB polarization imaging array are developed and compared to the current state of the art. These aspects include dual-polarization sensitivity, background-limited detection over a 10:1 bandwidth ratio, and frequency-independent angular responses. Although existing technology lacks all of this capability, today's CMB imaging arrays achieve many of these ideals and are highly advanced superconducting integrated circuits. Deployed arrays map the sky with pixels that contain elements for beam formation, polarization diplexing, passband definition in multiple frequency channels, and bolometric sensing. Several detector architectures are presented. We comment on the implementation of both transition-edge sensor bolometers and microwave kinetic inductance detectors for CMB applications. Lastly, we discuss fabrication capability in the context of next-generation instruments that call for ∼106 sensors.
Journal of Low Temperature Physics


low-temperature detector, LTD, cosmic microwave background, CMB, polarization experiments, imaging arrays, polarization measurements, dual-polarization sensitivity, background-limited detection, 10:1 bandwidth ratio, frequency-independent angular responses, pixels, beam formation, polarization duplexing, multiple frequency channels, bolometric sensing


Hubmayr, J. , Austermann, J. , Beall, J. , Becker, D. , Dober, B. , Duff, S. , Gao, J. , Hilton, G. , McKenney, C. , Ullom, J. , Van, J. and Vissers, M. (2018), Low-Temperature Detectors for CMB Imaging Arrays, Journal of Low Temperature Physics, [online], (Accessed May 24, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created August 3, 2018, Updated June 29, 2020