Accurate THz ellipsometry using calibration in time domain
Abstract We report on the realisation of a customized THz time domain spectroscopic ellipsometer (THz-TDSE) based on fiber-coupled photoconductive antennas, operating in a wide range of incident angles and allowing also standard transmission spectroscopy without any optical realignment. To ensure ac...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2022-05-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-022-10804-w |
| _version_ | 1817985337409929216 |
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| author | Zahra Mazaheri Can Koral Antonello Andreone |
| author_facet | Zahra Mazaheri Can Koral Antonello Andreone |
| author_sort | Zahra Mazaheri |
| collection | DOAJ |
| description | Abstract We report on the realisation of a customized THz time domain spectroscopic ellipsometer (THz-TDSE) based on fiber-coupled photoconductive antennas, operating in a wide range of incident angles and allowing also standard transmission spectroscopy without any optical realignment. To ensure accurate parameter extraction for a broad range of materials, we developed a fast and effective algorithm-assisted method to calibrate the setup and compensate for the nonideality in the response of the THz system. The procedure allows to minimise errors induced by imperfect response of the antennas and polarizers, imprecise setting of the impinging and receiving angles in the goniometric mechanical arms, and unavoidable mismatches in the THz beam optics. Differently from other calibration methods applied in the literature, our approach compares in time domain the ellipsometric derived electric field s- and p-polarised components at a given angle of incidence with the reconstructed ones, attained by using the complex dielectric function of a known sample. The calibrated response is determined with high precision by setting the system in transmission mode. In order to validate the technique, ellipsometric measurements have been carried out at various angle of incidences on a number of materials both in solid and liquid form, and their data compared with what obtained by conventional THz spectroscopy. Results show that THz-TDSE accompanied with an accurate calibration procedure is an effective technique for material characterization, especially in case of samples with a high absorption rate that are not easily investigated through transmission measurements. |
| first_indexed | 2024-04-13T23:56:44Z |
| format | Article |
| id | doaj.art-808a9e13c45c4ae0abaeb137f85fe2a4 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-04-13T23:56:44Z |
| publishDate | 2022-05-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-808a9e13c45c4ae0abaeb137f85fe2a42022-12-22T02:23:52ZengNature PortfolioScientific Reports2045-23222022-05-0112111010.1038/s41598-022-10804-wAccurate THz ellipsometry using calibration in time domainZahra Mazaheri0Can Koral1Antonello Andreone2Department of Physics “E. Pancini”, University of Naples “Federico II”Department of Physics “E. Pancini”, University of Naples “Federico II”Department of Physics “E. Pancini”, University of Naples “Federico II”Abstract We report on the realisation of a customized THz time domain spectroscopic ellipsometer (THz-TDSE) based on fiber-coupled photoconductive antennas, operating in a wide range of incident angles and allowing also standard transmission spectroscopy without any optical realignment. To ensure accurate parameter extraction for a broad range of materials, we developed a fast and effective algorithm-assisted method to calibrate the setup and compensate for the nonideality in the response of the THz system. The procedure allows to minimise errors induced by imperfect response of the antennas and polarizers, imprecise setting of the impinging and receiving angles in the goniometric mechanical arms, and unavoidable mismatches in the THz beam optics. Differently from other calibration methods applied in the literature, our approach compares in time domain the ellipsometric derived electric field s- and p-polarised components at a given angle of incidence with the reconstructed ones, attained by using the complex dielectric function of a known sample. The calibrated response is determined with high precision by setting the system in transmission mode. In order to validate the technique, ellipsometric measurements have been carried out at various angle of incidences on a number of materials both in solid and liquid form, and their data compared with what obtained by conventional THz spectroscopy. Results show that THz-TDSE accompanied with an accurate calibration procedure is an effective technique for material characterization, especially in case of samples with a high absorption rate that are not easily investigated through transmission measurements.https://doi.org/10.1038/s41598-022-10804-w |
| spellingShingle | Zahra Mazaheri Can Koral Antonello Andreone Accurate THz ellipsometry using calibration in time domain Scientific Reports |
| title | Accurate THz ellipsometry using calibration in time domain |
| title_full | Accurate THz ellipsometry using calibration in time domain |
| title_fullStr | Accurate THz ellipsometry using calibration in time domain |
| title_full_unstemmed | Accurate THz ellipsometry using calibration in time domain |
| title_short | Accurate THz ellipsometry using calibration in time domain |
| title_sort | accurate thz ellipsometry using calibration in time domain |
| url | https://doi.org/10.1038/s41598-022-10804-w |
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