Sub-10-fs deep-ultraviolet light source with stable power and spectrum.

Area of Science:

• Ultrafast spectroscopy
• Quantum optics
• Physical chemistry

Background:

• Ultrafast spectroscopy applications require highly stable sub-10-femtosecond (fs) pulses for extended durations (tens of minutes).
• Existing deep-ultraviolet (DUV) pulse generation methods may not consistently meet these stability requirements.
• Precise control over pulse spectrum and power is crucial for advanced spectroscopic measurements.

Purpose of the Study:

• To generate stable sub-10-fs deep-ultraviolet (DUV) pulses suitable for demanding ultrafast spectroscopy applications.
• To achieve high power stability (less than 3% root mean square fluctuation) in the generated DUV pulses.
• To demonstrate the utility of these stable DUV pulses in high-resolution transient absorption spectroscopy.

Main Methods:

• Generation of sub-10-fs DUV pulses via chirped-pulse four-wave mixing.
• Implementation of power stabilization schemes using a dedicated power stabilizer.
• Application of the generated pulses to transient absorption spectroscopy.

Main Results:

• Successfully generated sub-10-fs DUV pulses with high spectral and power stability.
• Achieved power fluctuations below 3% root mean square (rms) through stabilization techniques.
• Demonstrated sub-10-fs time resolution in DUV transient absorption spectroscopy experiments.
• The developed DUV source exhibits performance comparable to established noncollinear optical parametric amplifiers.

Conclusions:

• Chirped-pulse four-wave mixing is an effective method for generating stable sub-10-fs DUV pulses.
• The implemented stabilization schemes ensure reliable pulse characteristics for extended experimental runs.
• This stable DUV source significantly advances the capabilities of ultrafast spectroscopy, particularly for probing ultrafast dynamics in the DUV region.