Nonlinear terahertz-wave radiation generated by mid-infrared dual-chirped optical parametric amplification femtosecond pulse laser excitation

Kyuki Shibuya; Kouji Nawata; Yoshiaki Nakajima; Yuxi Fu; Eiji J. Takahashi; Katsumi Midorikawa; Takeshi Yasui; Hiroaki Minamide

arXiv · 2102.08631

Nonlinear terahertz-wave radiation generated by mid-infrared dual-chirped optical parametric amplification femtosecond pulse laser excitation

Kyuki Shibuya·Kouji Nawata·Yoshiaki Nakajima·Yuxi Fu·Eiji J. Takahashi·Katsumi Midorikawa·Takeshi Yasui·Hiroaki Minamide

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Abstract

We demonstrate an efficient procedure for terahertz-wave radiation generation by applying a nonlinear wavelength conversion approach using a mid-infrared pump source. We used a 3.3 μm dual-chirped optical parametric amplification source and a 1.5 μm fiber laser for a comparison of energy conversion efficiencies. Nonlinear inorganic and organic crystals were used, and for the periodically-poled lithium niobate crystal, the efficiencies were 1.3*10^-4 and 5.6*10^-12 for the 3.3 μm source and the 1.5 μm source, respectively. We confirmed that nonlinear crystals could be pumped with tera-watt / cm^2 class by using an mid-infrared source, which reduces several undesirable nonlinear optical effects.

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Kyuki Shibuya, Kouji Nawata, Yoshiaki Nakajima, Yuxi Fu, Eiji J. Takahashi, Katsumi Midorikawa, Takeshi Yasui, Hiroaki Minamide. 2021-02-17. Nonlinear terahertz-wave radiation generated by mid-infrared dual-chirped optical parametric amplification femtosecond pulse laser excitation. https://arxiv.org/abs/2102.08631

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