High-harmonic generation from a flat liquid-sheet plasma mirror.

Area of Science:

• Laser-plasma interactions
• Attosecond science
• Extreme ultraviolet and X-ray generation

Background:

• High-harmonic radiation (HHR) is generated by reflecting ultra-intense laser beams from over-dense plasmas (plasma mirrors).
• This technique is promising for generating intense attosecond pulses in the EUV and X-ray ranges.
• Solid targets used for plasma mirrors are damaged, limiting applications requiring extensive data acquisition.

Purpose of the Study:

• To demonstrate continuous high-harmonic radiation generation from a liquid plasma mirror.
• To overcome the limitations of solid targets in plasma mirror applications.
• To enable development of stable, high-repetition-rate attosecond light sources.

Main Methods:

• Utilizing a liquid target to form an over-dense plasma mirror.
• Investigating high-harmonic radiation generation in both coherent wake emission and relativistic oscillating mirror regimes.
• Characterizing the generated radiation from the liquid plasma mirror.

Main Results:

• Continuous generation of high-harmonic radiation was achieved from a liquid plasma mirror.
• Both coherent wake emission and relativistic oscillating mirror regimes were observed.
• The liquid plasma mirror approach circumvents the target damage issue inherent to solid targets.

Conclusions:

• Liquid plasma mirrors offer a viable alternative to solid targets for high-harmonic radiation generation.
• This advancement facilitates the creation of bright, stable, high-repetition-rate attosecond light sources.
• The findings significantly benefit research in ultrafast laser-matter interactions and related fields.