PTB sets benchmarks in terahertz radiometry
In 2015, these activities arrived at another very important result with the successful performance of an international pilot comparison on THz power measurement. The other two participants were the national metrology institutes of China and the USA which wanted to compare their THz radiometers with PTB’s. The excellent agreement resulting from this comparison has allowed PTB to extend its calibration services down to 0.7 THz with optical methods. New THz detectors have enabled this additional step; these were developed in collaboration with a German manufacturer over the past two years and have now been enhanced, so that the THz power of a time domain spectroscopy (TDS) system could be measured absolutely for the first time. All around the world, TDS systems are the “workhorses” in the field of THz; they are on the verge of being used for industrial applications and are therefore the main topic of the first VDI/VDE guidelines of the recently established VDI Committee “THz Systems”.