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20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
Dramatic enhancement of high-order harmonic generation.
Eiji J Takahashi1, Tsuneto Kanai, Kenichi L Ishikawa
1Laser Technology Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. ejtak@riken.jp
Physical Review Letters
|October 13, 2007
Summary
We enhanced high-order harmonic generation using mixed gases. Xenon harmonics boosted helium harmonic yield by 4,000 times, a significant finding for laser-matter interactions.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Optics
- Laser Physics
Background:
- High-order harmonic generation (HHG) is a crucial nonlinear optical process for producing coherent extreme ultraviolet and X-ray radiation.
- Previous studies focused on single-atom HHG, with limited enhancement strategies.
- Controlling and enhancing HHG is vital for applications in spectroscopy, imaging, and attosecond science.
Purpose of the Study:
- To investigate the enhancement of high-order harmonic generation (HHG) using simultaneous irradiation of booster harmonics.
- To explore the effect of mixed gases with different ionization potentials on HHG yield.
- To demonstrate a significant enhancement factor in HHG through a novel experimental approach.
Main Methods:
- Simultaneous irradiation of mixed gases (Xenon and Helium) with distinct ionization energies.
- Utilizing harmonics generated by Xenon atoms as a booster source for Helium HHG.
- Employing time-dependent Schrödinger equation simulations to model the observed phenomena.
- Analyzing the spatial characteristics and medium condition dependencies of the generated harmonics.
Main Results:
- Achieved a dramatic enhancement of HHG yield from Helium by a factor of 4 x 10^3.
- Demonstrated that Xenon harmonics effectively act as a booster, significantly increasing the harmonic yield from Helium.
- Experimental observations were corroborated by theoretical simulations, confirming the enhancement mechanism.
- Identified the dependence of the enhancement effect on medium conditions and spatial characteristics.
Conclusions:
- The simultaneous irradiation of booster harmonics in mixed gases provides a powerful method for dramatically enhancing high-order harmonic generation.
- This technique offers a significant increase in harmonic yield, opening new possibilities for efficient X-ray light generation.
- The findings are supported by theoretical modeling and experimental validation, highlighting the robustness of the enhancement mechanism.
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