Abstract-Measurable lower limit of thin film conductivity with parallel plate waveguide terahertz time domain spectroscopy

Manjakavahoaka Razanoelina, Shohei Ohashi, Iwao Kawayama, Hironaru Murakami, Annick F. Dégardin, Alain J. Kreisler, and Masayoshi Tonouchi

https://www.osapublishing.org/ol/abstract.cfm?uri=ol-42-15-3056&origin=search

Parallel plate waveguide (PPWG) terahertz (THz) time domain spectroscopy (TDS) is a powerful tool to investigate the properties of thin and low conductive materials. In this Letter, we determine the lower limit of detection of the PPWG–THz–TDS approach. We provide a closed-form expression of the minimal measurable conductivity by the system. The experimental results of amorphous YBa2Cu3O7−𝛿${\mathrm{YBa}}_2{\mathrm{Cu}}_3{\mathrm{O}}_{7-\delta }$ films indicate that the factor limiting the spectroscopic modality is the waveguide device misalignment. On the other hand, the expression of the minimal detectable conductivity provides a clear scheme of optimization by increasing the waveguide length and therefore enhancing the sensitivity of the system.

© 2017 Optical Society of America