Super resolution spectroscopy for THz-TDS: Application to Gas spectroscopy

Time Domain Spectroscopy resolution is usually limited by the Fourier Heisenberg criteria (FHC) coming from the length of the delay line. We will present a method to exploit THz-TDS spectra providing a ~ 10-fold resolution improvement reaching ~120 MHz for width measurements. These results were obtained by modeling and the implementation of a constraint reconstruction algorithm. We tested the methods on temporal traces from gaseous NH3 and were in very good agreement with the values from literature [1] down to a pressure of 5 mbar.