Photonic THz near-field imaging: Characterizing high-frequency components from 100 GHz to 4 THz

We present photonic terahertz (THz) near-field, frequency resolved measurements of high-frequency THz emitters from 100 GHz to 4 THz. Up to 528 GHz, we are able to accurately model our measurements with the finite element method for high-frequencies. For higher frequencies, modelling becomes too time consuming, thus stressing importance of measurements. Around 2 THz, we identify unwanted reflections from the air / submount interface.