Terahertz time-domain spectroscopy using a power detector

We here demonstrate the ability of a power detector implemented with a Michelson interferometer to perform spectral analysis in the THz range. Both analytical and experimental investigations are performed in the time domain. The polarization state of the impinging beam has been optimized and interfero-gram measurements are in a good agreement with the expected ones. Spectral response and spatial distribution (2D mapping) of the measurement bench have been characterized. Thanks to the wide bandwidth and a measurement dynamics of 40 dB, material spectroscopy and terahertz power detector analysis has been demonstrated.