Mechanisms for improved XeF laser performance at elevated temperatures

Area of Science:

• Laser Physics
• Spectroscopy
• Chemical Kinetics

Background:

• Ne/Xe/NF(3) gas mixtures are utilized in laser applications.
• Understanding laser efficiency dependence on temperature is crucial for optimization.
• Previous studies suggested ground-state dissociation and absorption influence efficiency.

Purpose of the Study:

• To measure lasing spectra and output efficiency of Ne/Xe/NF(3) laser mixtures across a temperature range.
• To identify specific rotational states contributing to narrowband emissions.
• To elucidate the primary mechanisms responsible for temperature-dependent laser efficiency.

Main Methods:

• Experimental measurement of lasing spectra and output efficiency for four Ne/Xe/NF(3) mixtures from 300 K to 450 K.
• High-resolution spectral analysis correlated with theoretical rotational bandhead structure.
• Identification of rotational states linked to 351-nm band emissions.

Main Results:

• Two narrowband emissions in the 351-nm band were identified and linked to specific rotational states.
• Rotational-vibrational population shifts were found to be the dominant factor increasing laser efficiency with temperature.
• The importance of increased ground-state dissociation and decreased narrowband absorption was re-evaluated and found to be less significant than previously thought.

Conclusions:

• Rotational-vibrational population shifts are the primary drivers of enhanced laser efficiency in Ne/Xe/NF(3) systems as temperature increases.
• The identified rotational states provide insight into the lasing mechanisms at 351 nm.
• This research refines the understanding of factors influencing Ne/Xe/NF(3) laser performance, highlighting population dynamics over dissociation and absorption effects.