Electrical and optical measurements on the first SCUBA-2 prototype 1280pixel submillimeter superconducting bolometer array

Abstract

SCUBA-2 is a submillimeter camera being built for the James Clerk Maxwell Telescope in Hawaii. Bringing CCD style imaging to the submillimeter for the first time, with over 10000 pixels, it will provide a revolutionary improvement in sensitivity and mapping speed. We present results of the first tests on a prototype 1280 pixel SCUBA-2 subarray; the full instrument will be made up of eight such subarrays. The array is made up of transition edge sensor (TES) detectors, with Mo/Cu bilayers as the sensing element. To keep the number of wires reasonable, a multiplexed readout is used. Unlike previous TES arrays, an in-focal plane multiplexer configuration is used, in which the multiplexing elements are located beneath each pixel. To achieve the required performance, the detectors are operated at a temperature of approximately 120 mK. We describe the results of a basic electrical and optical characterization of the array, demonstrating that it is fully operational. Noise measurements were made on several pixels and gave a noise equivalent power below 2.5 x 10(-17) W HZ(-0.5), within the requirements for SCUBA-2. The construction of the testbed used to carry out these measurements is also described.

Passive Submillimeter-wave Stand-off Video Camera for Security Applications

“…They can easily be arranged to large arrays [12] but require an expensive cooling system. However, the cost is independent of the number of detectors, becoming negligible for large arrays.…”

Mo-Based Proximity Bilayers for TES: Microstructure and Properties

“…The most studied and with best spectral resolution TES have Ti or Mo as superconductor, and Cu or Au as normal metal [4]- [7]. While Ti/Au bilayers may suffer aging problems [8], Mo/Au bilayers display excellent chemical stability to stand the required conditions for detectors in spacecrafts [9].…”

Optical requirements and modeling of coupling devices for future far-infrared space missions

“…Silicon nitride thermal isolation was originally developed for ground-based and balloon-borne mm-wave instruments (SuZIE, BOOMERANG, BOLOCAM, BLAST), and later adapted for use in the PLANCK-HFI [1] and HERSCHEL-SPIRE [2] instruments, as well as in all of the current ground-based and balloon-borne instruments such as SCUBA2 and CLOVER. The rapid development of TESs over the last decade TES technology has increased its technology readiness level, and has paved the way for use on future space missions such as B-Pol, SPICA, and FIRI.…”