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

TL;DR

This paper demonstrates the generation of a coherent, octave-spanning soft X-ray supercontinuum producing single-cycle attosecond pulses using advanced mid-infrared pulses, with potential applications in ultrafast science.

Contribution

It introduces a method to produce single-cycle soft X-ray pulses via supercontinuum high harmonic generation with dispersion compensation, advancing ultrafast X-ray science.

Findings

Generated supercontinuum high harmonic spectra in argon and neon.

Achieved 40 as pulses in argon and 23 as pulses in neon after dispersion compensation.

Experimental results agree with theoretical models.

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.