Sub-2 fs pulses generated by self-channeling in the deep ultraviolet

Area of Science:

• Ultrafast optics
• Nonlinear optics
• Plasma physics

Background:

• Generating ultrashort light pulses is crucial for high-resolution spectroscopy and advanced imaging.
• Existing methods often face limitations in pulse duration and stability, especially in the ultraviolet spectrum.

Purpose of the Study:

• To numerically demonstrate the generation of sub-2 femtosecond (fs) light pulses in the ultraviolet (UV) spectrum.
• To investigate the propagation dynamics and stability of these ultrashort pulses.

Main Methods:

• Numerical simulation of nonlinear optical propagation.
• Frequency conversion via Kerr self-focusing in a filamentation regime.
• Modeling the interaction of light pulses with a low-density plasma.

Main Results:

• Successfully generated UV light pulses with durations below 2 fs.
• Demonstrated that few-cycle pulses at 266 nm maintain their temporal shape over tens of centimeters.
• Observed pulse self-compression resulting from the combined effects of Kerr self-focusing and plasma defocusing.

Conclusions:

• The proposed method offers a viable route for generating extreme UV ultrashort pulses.
• The interplay between Kerr nonlinearity and plasma dynamics is key to achieving stable pulse propagation and compression.
• This technique holds promise for applications requiring high peak power UV light sources.