Title Integrated diffractive optical elements for terahertz beam shaping and polarization control /
Translation of Title Integriniai difrakciniai optiniai elementai terahercinio pluošto formavimui ir poliarizacijos valdymui.
Authors Ayyagari, Surya Revanth
DOI 10.15388/vu.thesis.756
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Pages 107
Keywords [eng] diffractive optical elements ; hybrid multi-phase Fresnel zone plate ; high contrast grating ; free-standing meta-surfaces
Abstract [eng] This doctoral dissertation presents the design, development, and optimization of integrated diffractive optical elements (DOEs) for efficient beam focusing, polarization control and enhanced transparency in the terahertz (THz) frequency range (0.1–1 THz). Utilizing semiconductor- and metal-based elements, the research introduces hybrid multi-phase Fresnel zone plate (H-MPZP) lenses with reduced structural complexity and enhanced focusing performance, high contrast grating (HCG) waveplates with sinusoidal surface modulation for broadband polarization manipulation, and free-standing meta-surfaces composed of subwavelength resonators engineered to exploit electromagnetic coupling and anapole resonances for enhanced transparency and spectral control. Numerical simulations and experimental validations confirm the capability of these compact, lightweight, and integrable elements to deliver high efficiency, reduced reflection losses, and wide operational bandwidths. These findings offer promising pathways for advancing THz photonics in imaging, sensing, communication technologies, and semiconductor-integrated on-chip platforms.
Dissertation Institution Vilniaus universitetas.
Type Doctoral thesis
Language English
Publication date 2025