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arXiv · 1110.6505

Comparative investigation of third and fifth harmonic generation in atomic and molecular gases driven by mid-infrared ultrafast laser pulses

Jielei Ni·Jinping Yao·Bin Zeng·Wei Chu·Guihua Li·Haisu Zhang·Chenrui Jing·See Leang Chin·Ya Cheng·Zhizhan Xu
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Abstract

We report on the comparative experimental investigation on third and fifth harmonic generation (THG and FHG) in atomic and molecular gases driven by mid-infrared ultrafast laser pulses at a wavelength of ~1500 nm. We observe that the conversion efficiencies of both the THG and FHG processes saturate at similar peak intensities close to ~1.5\times1014 W/cm2 for argon, nitrogen, and air, whose ionization potentials are close to each other. Near the saturation intensity, the ratio of yields of the FHG and THG reaches ~10-1 for all the gases. Our results show that high-order Kerr effects do exist, whereas they are insufficient to balance the Kerr self-focusing without the assistance of plasma generation.

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Jielei Ni, Jinping Yao, Bin Zeng, Wei Chu, Guihua Li, Haisu Zhang, Chenrui Jing, See Leang Chin, Ya Cheng, Zhizhan Xu. 2011-10-29. Comparative investigation of third and fifth harmonic generation in atomic and molecular gases driven by mid-infrared ultrafast laser pulses. https://doi.org/10.1103/physreva.84.063846

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