{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T01:04:56Z","timestamp":1768525496651,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2024,6,30]],"date-time":"2024-06-30T00:00:00Z","timestamp":1719705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union","doi-asserted-by":"publisher","award":["10104665"],"award-info":[{"award-number":["10104665"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The generation of terahertz radiation via laser-induced plasma from two-color femtosecond pulses in air has been extensively studied due to its broad emission spectrum and significant pulse energy. However, precise control over the temporal properties of these ultra-broadband terahertz pulses, as well as the measurement of their polarization state, remain challenging. In this study, we review our latest findings on these topics and present additional results not previously reported in our earlier works. First, we investigate the impact of chirping on the fundamental wave and the effect of manipulating the phase difference between the fundamental wave and the second-harmonic wave on the properties of generated terahertz pulses. We demonstrate that we can tune the time shape of terahertz pulses, causing them to reverse polarity or become bipolar by carefully selecting the correct combination of chirp and phase. Additionally, we introduce a novel technique for polarization characterization, termed terahertz unipolar polarimetry, which utilizes a weak probe beam and avoids the systematic errors associated with traditional methods. This technique is effective for detecting polarization-structured terahertz beams and the longitudinal component of focused terahertz beams. Our findings contribute to the improved control and characterization of terahertz radiation, enhancing its application in fields such as nonlinear optics, spectroscopy, and microscopy.<\/jats:p>","DOI":"10.3390\/s24134265","type":"journal-article","created":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T10:14:46Z","timestamp":1719828886000},"page":"4265","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["THz Generation by Two-Color Plasma: Time Shaping and Ultra-Broadband Polarimetry"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7745-230X","authenticated-orcid":false,"given":"Domenico","family":"Paparo","sequence":"first","affiliation":[{"name":"ISASI\u2014Institute of Applied Sciences and Intelligent Systems, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli, Italy"},{"name":"Dipartimento di Fisica \u201cEttore Pancini\u201d, Universit\u00e0 di Napoli \u201cFederico II\u201d, Complesso Universitario di Monte Sant\u2019Angelo, via Cintia, 80126 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-2076-5000","authenticated-orcid":false,"given":"Anna","family":"Martinez","sequence":"additional","affiliation":[{"name":"ISASI\u2014Institute of Applied Sciences and Intelligent Systems, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli, Italy"},{"name":"Dipartimento di Fisica \u201cEttore Pancini\u201d, Universit\u00e0 di Napoli \u201cFederico II\u201d, Complesso Universitario di Monte Sant\u2019Angelo, via Cintia, 80126 Napoli, Italy"},{"name":"Scuola Superiore Meridionale, Largo San Marcellino, 80138 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9689-615X","authenticated-orcid":false,"given":"Andrea","family":"Rubano","sequence":"additional","affiliation":[{"name":"ISASI\u2014Institute of Applied Sciences and Intelligent Systems, Consiglio Nazionale delle Ricerche, via Campi Flegrei 34, 80078 Pozzuoli, Italy"},{"name":"Dipartimento di Fisica \u201cEttore Pancini\u201d, Universit\u00e0 di Napoli \u201cFederico II\u201d, Complesso Universitario di Monte Sant\u2019Angelo, via Cintia, 80126 Napoli, Italy"}]},{"given":"Jonathan","family":"Houard","sequence":"additional","affiliation":[{"name":"University Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie University, GPM UMR 6634, F-76000 Rouen, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4357-7032","authenticated-orcid":false,"given":"Ammar","family":"Hideur","sequence":"additional","affiliation":[{"name":"CORIA CNRS, INSA, Universit\u00e9 de Rouen Normandie, F-76801 Saint Etienne du Rouvray, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1501-159X","authenticated-orcid":false,"given":"Angela","family":"Vella","sequence":"additional","affiliation":[{"name":"University Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie University, GPM UMR 6634, F-76000 Rouen, France"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1210","DOI":"10.1364\/OL.25.001210","article-title":"Intense terahertz pulses by four-wave rectification in air","volume":"25","author":"Cook","year":"2000","journal-title":"Opt. 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