%0 Journal Article
%T Superconducting hot-electron nanobolometer with microwave bias and readout
%A A. A. Kuzmin
%A M. Merker
%A S. V. Shitov
%A N. N. Abramov
%A A. B. Ermakov
%A M. Arndt
%A S. H. Wuensch
%A K. S. Ilin
%A A. V. Ustinov
%A M Siegel
%J Physics
%D 2014
%I arXiv
%X We propose a new detection technique based on radio-frequency (RF) bias and readout of an antenna-coupled superconducting nanobolometer. This approach is suitable for Frequency-Division-Multiplexing (FDM) readout of large arrays using broadband low-noise RF amplifier. We call this new detector RFTES. This feasibility study was made on demonstrator devices which are made in all-Nb technology and operate at 4.2 K. The studied RFTES devices consist of an antenna-coupled superconducting nanobolometer made of ultrathin niobium films with transition temperature Tc = 5.2 K. The 0.65-THz antenna and nanobolometer are embedded as a load into a GHz-range coplanar niobium resonator (Tc = 8.9 K, Q = 4000). To heat the superconducting Nb nanobolometer close to the Tc, the RF power at resonator frequency f = 5.8 GHz is applied via a transmission line which is weakly coupled (-11 dB) to the loaded resonator. The THz-antenna of RFTES was placed in the focus of a sapphire immersion lens inside a He4-cryostat equipped with an optical window and a semiconductor RF amplifier. We have demonstrated optical response of the RFTES to THz radiation. The demonstrator receiver system employing the RFTES device showed an optical Noise-Equivalent Power (NEP) 1e-14 W/sqrt(Hz) at 4.2 K.
%U http://arxiv.org/abs/1412.4502v1