The Future of Airborne Infrared/Submm Astronomy: Instrument Solutions

Zieger

2-08

Gabriel Zieger, M. Schmelz, K. Peiselt, O. Brandel, D. Born, E. Heinz, J. Kunert, M. Siegel, V. Zakosarenko, M. Meyer, R. Stolz
Leibniz Institute of Photonic Technology, Deptm. Quantum systems; Supracon AG; Institute of Micro- and Nanoelectronic Systems, KIT

Transition Edge Sensors and Multiplexing Readout for IR/Sub-mm Applications

Superconducting  Transition  Edge  Sensors  (TES)  offer  a  wide  range  of  applications:  Bolometers  and
calorimeters equipped with TES can be tuned by design in a wide spectral range from microwaves to
x-rays. Broad band as well as narrow band absorption is achievable with high efficiency. The  very  high  linearity  of  the  output  signal  allows  for  high  bit  depth  measurements.  Hence,  setups
operating  with  varying  background  levels  can  be  achieved,  which  simplify  calibration  efforts  and
enable  continuous  measurements  under  strongly  varying  signal  levels.  Depending  on  application
requirements, the cooling level can be adequately adjusted to achieve the required noise equivalent
power (NEP) e.g. to enable background limited infrared photodetection (BLIP) mode. We show different examples of application scenarios for TES, the development and fabrication of TES
as  well  as  amplification  and  multiplexing  read  out  circuits  at  Leibniz-IPHT  as  basis  for  precise
matching of the detector and readout for the application needs. As an example of the scalability of these components, we present results from the development of a
security  gate  camera  showing  video  rate  imaging  at  THz  wavelengths.  The  system  is  optimized  for
stand-off detection up to 25m with an auto focus  objective.  Aiming for a wide dissemination of this
detection  technology,  focus  has  been  laid  on  a  compact  closed-cycle  cooling  system  with  a  base
temperature of about  1K, enabling to leave out expensive 3He cooling, while maintaining necessary
noise performance of the TES. Microwave SQUID multiplexer are designed to read out the 128 feed-
horn coupled aluminum TES and present a robust and scalable technology. By adopting this
technology to the specific needs, a wide range of applications can be addressed in future.  The  work  was  funded  by  the  Federal  Ministry  of  Education  and  Research  in  the  framework  of  the
project “Multimodal  Remote  Detection  of  Hidden  Threats  in  People  Screening” under  grants  no.
13N14713 and 13N14712 (HiTD).