[11p-C213-1~9] 3.5 Ultrashort-pulse and high-intensity lasers

4:15 PM - 4:30 PM JST(7:15 AM - 7:30 AM UTC)

[11p-C213-9] Cumulative effects in 100 kHz class high repetition rate high harmonic generation

〇(M2)Hotaka Yamada^1,2, Kohei Nagai¹, Takuya Okamoto¹, Yasushi Shinohara¹, Ikufumi Katayama², Jun Takeda³, Haruki Sanada¹, Katsuya Oguri¹ (1.NTT-BRL, 2.Yokohama Natl. Univ., 3.SIT research labs., Shibaura Inst. of Tech.)

Keywords:

high harmonic generation

Bright high-harmonic generation (HHG) sources in the extreme-ultraviolet region are needed for applications such as photoelectron spectroscopy and coherent diffraction imaging. Although recent advances in Yb amplifier and chirped-pulse amplification technologies have enabled high-repetition-rate HHG, the repetition-rate dependence of HHG yield near 100 kHz has not been well understood. Here, we used a tunable Yb regenerative amplifier operating at 10–100 kHz to measure HHG in argon. 1030 nm, 500 μJ pulses were compressed to 50 fs and focused to a peak intensity of 1.5 × 10¹⁴ W/cm². The HHG yield increased with repetition rate. Numerical simulations indicate that pulse-train-induced low-density channels reduce plasma defocusing, raise the peak intensity, and enhance harmonic output.