Sub-15fs ultraviolet pulses generated by achromatic phase-matching sum-frequency mixing

Area of Science:

• Ultrafast optics
• Nonlinear optics
• Laser physics

Background:

• Generating broadband ultraviolet (UV) light is crucial for various spectroscopic and photochemical applications.
• Existing methods for UV pulse generation often face limitations in spectral width, pulse duration, or energy.
• Ultrashort pulse generation requires precise control over phase matching and dispersion.

Purpose of the Study:

• To develop a method for generating broadband ultraviolet pulses with a wide spectral width.
• To achieve ultrashort pulse durations for the generated UV light.
• To optimize the energy of the produced UV pulses.

Main Methods:

• Achromatic sum-frequency mixing of an 805-nm pulse and an ultrabroadband visible pulse was employed.
• Angular dispersion was introduced using a prism pair to achieve broadband phase matching.
• A second prism pair was utilized for temporal compression of the UV pulse.

Main Results:

• A broadband ultraviolet pulse with a spectral width of 44 nm was successfully generated.
• The UV pulse was compressed to an ultrashort duration of 13.2 femtoseconds.
• The generated UV pulse achieved an energy of 600 nJ.

Conclusions:

• Achromatic sum-frequency mixing provides an effective route for generating broadband, ultrashort UV pulses.
• The developed method demonstrates precise control over phase matching and pulse compression.
• The high-energy, femtosecond UV pulses are suitable for advanced applications in spectroscopy and materials science.