Diode-laser infrared heterodyne radiometer at 28 μm

摘要

An infrared heterodyne radiometer has been constructed which operates at 28 μm with a PbSnSe diode laser local oscillator and a HgCdTe photodiode photomixer, both cooled to about 20 K. In spite of low power and excess noise of the diode laser and weak rectification characteristics of the photodiode, a heterodyne NEP of 3.5 × 10⁻¹⁹ W/Hz was measured over a bandwidth of 500 MHz.