A comparison of terahertz power measurements at sub-microwatt levels

In this paper, we compare absolute power measurements obtained at 1 THz using a newly proposed terahertz (THz) calorimeter and a commercial power meter. The experimental measurement was performed at a sub-microwatt level using a photomixer as the THz source. Using the calorimeter, we obtained highly sensitive measurement results with good accuracy at room temperature of 23°C, and there was good agreement with the result from the commercial power meter.