Optical Response of Strained- and Unstrained-Silicon Cold-Electron   Bolometers
  We describe the optical characterisation of two silicon cold-electron bolometers each consisting of a small ($32 \times 14~\mathrm{\mu m}$) island of degenerately doped silicon with superconducting aluminium contacts. Radiation is coupled into the silicon absorber with a twin-slot antenna designed to couple to 160-GHz radiation through a silicon lens.The first device has a highly doped silicon absorber, the second has a highly doped strained-silicon absorber.Using a novel method of cross-correlating the outputs from two parallel amplifiers, we measure noise-equivalent powers of $3.0 \times 10^{-16}$ and $6.6 \times 10^{-17}~\mathrm{W\,Hz^{-1/2}}$ for the control and strained device, respectively, when observing radiation from a 77-K source. In the case of the strained device, the noise-equivalent power is limited by the photon noise. 
T. L. R. Brien, P. A. R. Ade, P. S. Barry, C. J. Dunscombe, D. R.   Leadley, D. V. Morozov, M. Myronov, E. H. C. Parker, M. ...
astro-ph.IM physics.ins-det