Complex refractive index determination of PTFE, TPX and polypropylene windows for TeraHertz broadband spectroscopy

We perform TeraHertz characterization of three low-loss polymer candidates, i.e. polytetrafluoroethylene, polymethylpentene, and polypropylene, to choose the material with the proper opto-mechanical properties for aerosol and gas broadband spectroscopy cell windows. Samples are analyzed with the TeraHertz time domain spectroscopy technique. Then, the time-traces are fitted with theoretical models and the real and imaginary parts of their complex refractive indices are extracted using the Fit@TDS algorithm developed by Photonic TeraHertz team members.