Terahertz mixing in MgB2 microbolometers

Abstract

The authors report on a terahertz (600GHz) mixing experiment with MgB2 microbolometers in the resistive state. The authors observed that for a 20nm film a mixer gain bandwidth of 2.3GHz can be achieved, corresponding to an energy relaxation time of 70ps. The experimental results were analyzed using a two-temperature model. As a result, the phonon escape time of ∼20ps was deduced. At 1.6THz the MgB2 mixer uncorrected noise temperature was 11000K. The obtained results show that MgB2 bolometers are good prospects for the terahertz range as both broadband mixers and fast direct detectors.