Macroscopic effects in generation of attosecond XUV pulses via high-order frequency mixing in gases and plasma

• DOI: 10.48550/arxiv.2308.02251
• Publication Date: 2023-01-01
• Authors: V. A. Birulia; M. A. Khokhlova; V. V. Strelkov
• Keywords: Attosecond; Extreme ultraviolet

We study the generation of attosecond XUV pulses via high-order frequency mixing (HFM) two intense generating fields, and compare this process with more common harmonic (HHG) process. calculate macroscopic signal by numerically integrating 1D propagation equation coupled 3D time-dependent Schr\"odinger equation. analytically find length scales which limit quadratic growth HFM length. Compared to HHG these are much longer for a group components, orders defined frequencies fields. This results in higher despite microscopic response being lower than HHG. In our numerical simulations, intensity is several times that gas, it up three magnitude plasma; also pulses. The provides very narrow lines ($\delta \omega / = 4.6 \times 10^{-4}$) well-defined frequencies, thus allowing simple extension optical standards range. Finally, we show components effectively generated due effects train such carrier-envelope phase an individual pulse can be easily controlled tuning one