PT Journal
AU Jian Wei
   David Olaya
   Boris Karasik
   Sergey Pereverzev
   Andrei Sergeev
   Michael Gershenson
TI Ultra-sensitive hot-electron nanobolometers for terahertz astrophysics
SO ArXiv e-prints
PY 2007
VL 710
DE cond-mat.other; astro-ph; cond-mat.mes-hall
AB The background-limited spectral imaging of the early Universe requires spaceborne terahertz (THz) detectors with the sensitivity 2-3 orders of magnitude better than that of the state-of-the-art bolometers. To realize this sensitivity without sacrificing operating speed, novel detector designs should combine an ultrasmall heat capacity of a sensor with its unique thermal isolation. Quantum effects in thermal transport at nanoscale put strong limitations on the further improvement of traditional membrane-supported bolometers. Here we demonstrate an innovative approach by developing superconducting hot-electron nanobolometers in which the electrons are cooled only due to a weak electron-phonon interaction. At T<0.1K, the electron-phonon thermal conductance in these nanodevices becomes less than one percent of the quantum of thermal conductance. The hot-electron nanobolometers, sufficiently sensitive for registering single THz photons, are very promising for submillimeter astronomy and other applications based on quantum calorimetry and photon counting.
ER