Dependence of ultimate sensitivity of cold-electron bolometer on bath
temperature and signal power
M. Tarasov 1,
V. Edelman 2,
S. Mahashabde 3, L. Kuzmin
3
1
Kotelnikov Institute of Radio Engineering and Electronics,
2 Kapitza
Institute for Physical Problems,
3 Chalmers University of
Technology
The paper is received
on December 9, 2014
Abstract. Integrated structures
comprising cold electron bolometers and twin-slot antennas have been studied in
the temperature range 0.06-3 K. Dynamic resistance ratio and optical response was
measured for 2-15 K black body radiation temperature. For radiation
temperature of 2.7 K, which corresponds to cosmic microwave radiation
temperature, the optical responsivity was around 0.3*109 V/W and
temperature sensitivity of 2*10-4 Ê/Hz1/2. Ratio of irradiated and measured power
corresponds to matching efficiency of 0.6. For obtaining of Noise Equivalent
Power NEP=2*10-18 W/Hz1/2, that is required for many
space-borne experiments, the temperature of sample should be below 0.1 Ê, background radiation temperature
below 1.6 Ê, signal power below
1 fW at signal frequency 350 GHz, bandwidth 100 GHz and absorber
volume 5*10-20 m3. Such requirements are not realistic
for practical cases and to avoid saturation of receiver the arrays of
bolometers should be used instead of a single bolometer. For measurements of
signal in the range of 10-100 pW the array should consist of over 10-100
bolometers. Oral presentation
at The First Russian Microwave Conference, 27-29 November 2013, Moscow.
Key words: superconducting bolometers,
noise equivalent power, responsivity, background radiation temperature.
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