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arXiv · 2407.18543

Octave-spanning supercontinuum coherent soft X-ray for producing a single-cycle soft X-ray pulse

Kaito Nishimiya·Feng Wang·Pengfei Lan·Eiji J. Takahashi
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Abstract

This study demonstrates the potential to generate a soft X-ray single-cycle attosecond pulse using a single-cycle mid-infrared pulse from the advanced dual-chirped optical parametric amplification. Supercontinuum high harmonic (HH) spectrum was generated in argon (80 eV - 160 eV) and neon (150 eV - 270 eV). The experimental spectra reasonably agree with those calculated by the strong-field approximation model and Maxwell's equations. In addition, simulation results indicate that the dispersion of HHs in argon can be compensated using a 207-nm Zr filter to obtain 40 as pulses (1.1 cycles at 118 eV). For neon, a 278-nm Sn filter can compensate for dispersion of HH and create 23 as pulses (1.1 cycles at 206 eV). This soft X-ray single-cycle attosecond pulse is expected to be highly valuable for ultrafast science and applications in quantum information science.

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Kaito Nishimiya, Feng Wang, Pengfei Lan, Eiji J. Takahashi. 2024-07-26. Octave-spanning supercontinuum coherent soft X-ray for producing a single-cycle soft X-ray pulse. https://doi.org/10.1364/ol.537880

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