title: Wideband THz time domain spectroscopy based on optical rectification and electro-optic sampling.
abstract: We present an analytical model describing the full electromagnetic propagation in a THz time-domain spectroscopy (THz-TDS) system, from the THz pulses via Optical Rectification to the detection via Electro Optic-Sampling. While several investigations deal singularly with the many elements that constitute a THz-TDS, in our work we pay particular attention to the modelling of the time-frequency behaviour of all the stages which compose the experimental set-up. Therefore, our model considers the following main aspects: (i) pump beam focusing into the generation crystal; (ii) phase-matching inside both the generation and detection crystals; (iii) chromatic dispersion and absorption inside the crystals; (iv) Fabry-Perot effect; (v) diffraction outside, i.e. along the propagation, (vi) focalization and overlapping between THz and probe beams, (vii) electro-optic sampling. In order to validate our model, we report on the comparison between the simulations and the experimental data obtained from the same set-up, showing their good agreement.
authors.affiliation: DEIM, University of Palermo, Viale delle Scienze Bldg. 9, 90128, Palermo, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Tomasino
authors.forename: A
authors.initials: A
authors.lastname: Parisi
authors.forename: S
authors.initials: S
authors.lastname: Stivala
authors.forename: P
authors.initials: P
authors.lastname: Livreri
authors.forename: A C
authors.initials: AC
authors.lastname: Cino
authors.forename: A C
authors.initials: AC
authors.lastname: Busacca
authors.forename: M
authors.initials: M
authors.lastname: Peccianti
authors.forename: R
authors.initials: R
authors.lastname: Morandotti