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Information × Registration Number 0226U002837, (0124U000466) , R & D reports Title Electrodynamics of vortex laser beams in the terahertz range popup.stage_title Створення експериментальних установок і зразків приймачів для дослідження формування, поширення та фокусування вихрових лазерних пучків. Head Dehtiarov Andrii V., Кандидат фізико-математичних наук Registration Date 07-03-2026 Organization V.N. Karazin Kharkiv National University popup.description1 The main goal of the project is to propose new and effective intra-resonator and extra-resonator methods of forming vortex laser beams of continuous radiation in the terahertz range, to establish the physical features of their propagation and focusing. popup.description2 An optically pumped terahertz waveguide laser has been developed to generate radiation with spatially uniform and inhomogeneous polarization. An experimental setup has been created to study the energy, phase, and polarization characteristics of continuous laser radiation. Experimental studies were conducted at wavelengths of 432.6 and 118.8 μm. Experimental prototypes of receiving devices (detectors) capable of measuring the parameters of continuous laser terahertz beams with a phase front singularity (optical vortex) have been developed and manufactured. This allows recording the spatial intensity distribution and phase topology of vortex beams, which is a necessary condition for their identification and further practical application in photonics. Experiments were conducted with phase diffraction structures based on Rohacell 71HF - a material widely used for research in the microwave range. For the first time, the experimental transmission coefficient of continuous laser radiation at a wavelength of 118.8 μm through a 10 mm thick Rohacell 71HF material was determined, which is 20%. This material was used to create spiral phase plates. Due to the high level of absorption of laser radiation at this wavelength, further experiments were moved to a length of 432.6 μm. It is proposed to use polymer materials available in Ukraine for experiments in the terahertz range with phase diffraction structures: polyethylene (HDPE) PE-500, high molecular weight polyethylene (UHMWPE) PE-1000, polytetrafluoroethylene (PTFE or Teflon). The transmission coefficient of continuous laser radiation at a wavelength of 432.6 μm of these materials was determined for the first time. Spiral phase plate designs with different topological charges from the specified materials were developed and manufactured for conducting experiments in the next stage of work. Product Description popup.authors Mykhailo I. Dziubenko Vladyslav S. Seniuta Mykola H. Kokodii Oleksandr M. Levchenko Valerii M. Riabykh Oleh V. Hurin Oleh О. Svystunov Viacheslav O. Maslov popup.nrat_date 2026-03-07 Close