Quantum effects in the hot electron microbolometer

The theory of the hot electron microbolometer proposed by Nahum et al. assumed that the photon energy is thermalized in the electrons in the Cu absorber before relaxing to the lattice. Since the photons initially excite individual electrons to /spl planck//spl omega//spl Gt/k/sub B/T, however, direct relaxation of these hot electrons to phonons must also be considered, Theoretical estimates suggest that this extra relaxation channel increases the effective thermal conductance for /spl planck//spl omega//spl Gt/k/sub B/T and influences bolometer noise. Calculations of these effects are presented which predict very useful performance both for ground-based and space-based astronomical photometry at millimeter and submillimeter wavelengths.<>