"JOURNAL OF RADIO ELECTRONICS"  N 1, 2014

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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.