[21a-211A-1~11] 3.6 Ultrashort-pulse and high-intensity lasers

[21a-211A-9] Soft X-ray high-harmonic generation covering the entire water window

〇(M2)Hiroki Sannohe¹, Nariyuki Saito¹, Nobuhisa Ishii¹, Teruto Kanai¹, Jiro Itatani¹ (1.Tokyo Univ.)

Keywords:high-harmonic generation

In high-harmonic generation using a long-wavelength infrared light source, it is necessary to increase the pressure of the target gas to satisfy the phase matching condition.By using a newly developed high-pressure gas cell with a differential pumping system and intense infrared pulses at 1600 nm, we generate soft X-ray high harmonics which almost cover the entire "water window" region spanning from the carbon K-edge (284 eV) to the oxygen K-edge (543 eV). We also conduct an X-ray absorption measurement of titanium at the L_2,3-edge (460 eV) with the generated high harmonics.