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arXiv · 1912.08979

Generation of high-quality terahertz OAM mode based on soft-aperture difference frequency generation

Katsuhiko Miyamoto·Kazuki Sano·Takahiro Miyakawa·Hiromasa Niinomi·Kohei Toyoda·Adam Valles·Takashige Omatsu
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Abstract

We demonstrate the generation of high-quality tunable terahertz (THz) vortices in an eigenmode by employing soft-aperture difference frequency generation of a vortex output and a Gaussian mode. The generated THz vortex output exhibits a high-quality orbital angular momentum (OAM) mode with a topological charge of $\ell_{THz}=\pm1$ in a frequency range of 2-6 THz. The maximum average power of the THz vortex output obtained was ~3.3 $\mu$W at 4 THz.

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Katsuhiko Miyamoto, Kazuki Sano, Takahiro Miyakawa, Hiromasa Niinomi, Kohei Toyoda, Adam Valles, Takashige Omatsu. 2019-12-19. Generation of high-quality terahertz OAM mode based on soft-aperture difference frequency generation. https://doi.org/10.1364/oe.27.031840

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