Cryogenic bolometer with suspended absorber

 

M.Tarasov^1,2,4, V.Edelman², M.Fominsky¹, R.Yusupov^1,3, A.Yurgens⁴ 

¹ Kotelnikov Institute of Radio Engineering and Electronics  RAS

² Kapitza Institute for Physical Problems RAS

³ Moscow Institute of Physics and Technology (State University)

⁴ Chalmers University of Technology

 

 The paper is received on January 18, 2016

 

Abstract. A robust and simple technology for making suspended normal-metal (N) thin film bridges between superconducting (S) aluminum electrodes with tunnel barriers (I) was developed.  The bridges represent effective bolometer absorbers with reduced heat losses to substrates.  Such SINIS bolometers integrated with planar antennas are intended for operation in the THz-range of radiation.  Samples with different absorber materials were fabricated and current-voltage characteristics were measured at mK temperatures.  Samples with Cu absorber demonstrate a high sub-gap resistance that makes them competitive to conventional detectors. Potentially, such bolometers can improve the optical responsivity by an order of magnitude, up to 10⁹ V/W, as estimated from the equivalent dc power response in earlier prototypes.  

Keywords: SIN junction, bolometer, manufacturing suspended structures.