Flexible control over polarization tuning using electric wiggler during terahertz generation

• Published in: Optics and lasers in engineering 2023-08, Vol.167, p.107589, Article 107589
• Main Authors: Manendra, Singh, Kunwar Pal, Jewariya, Mukesh, Chaudhary, Pradeep, Malik, Anil K
• Format: Article
• Language: English
• Subjects: Electric wiggler biasing; Laser; Photo-mixing; THz polarization
• ISSN: 0143-8166; 1873-0302
• DOI: 10.1016/j.optlaseng.2023.107589

•New method for manipulation of THz polarization (linear-circular-elliptical) during Terahertz generation process.•Electric wiggler field is first time investigated for manipulation of THZ polarization, which has potential applications such as polarization-specific terahertz (THz) detection of human colonic excisions, line-of-sight telecommunication and information encryption.•Phase matching is achieved with the help of plasma corrugation.•Perfect control over ellipticity. Polarization of electromagnetic (EM) waves conveys remarkable information in sensitive terahertz (THz) measurements and communications. The conventional methods attain only limited performance over polarization control. Here, we report a powerful method for manipulation of THz polarization (linear-circular-elliptical) during the generation process. The THz wave is excited by photo-mixing of linearly polarized Gaussian lasers in a nonuniform plasma in the presence of external wiggler electric field. The state of THz polarization is tailored with electric wiggler biasing’s help. We find that emitted THz is linearly polarized for zero electric bias, circularly polarized for 15kV/cm wiggler field and elliptically polarized for 0−30kV/cm. We also find that direction of rotation of THz electric field vector depends on the polarity of electric wiggler. THz field ∼1.5×104kV/cm is obtained for laser intensity IL=2.98×1013W/cm2.