A tunable picosecond dye laser for use in dioxin analysis

Area of Science:

• Optics and Photonics
• Laser Physics
• Analytical Chemistry

Background:

• Development of tunable picosecond lasers is crucial for high-resolution spectroscopic applications.
• Existing laser systems may lack the required spectral purity and energy output for sensitive trace analysis.
• Dye lasers offer tunability but often face challenges in pulse stability and linewidth control.

Purpose of the Study:

• To design and construct a distributed-feedback dye laser system capable of generating tunable picosecond pulses.
• To achieve a narrow spectral linewidth and high pulse energy for advanced analytical applications.
• To evaluate the laser's suitability for trace analysis of dioxins via supersonic jet/resonance-enhanced multiphoton ionization/mass spectrometry.

Main Methods:

• A distributed-feedback dye laser with a quenching cavity was designed and built.
• A triple-pass off-axis amplifier was used to amplify the generated picosecond pulses.
• Second-harmonic generation was employed to double the frequency of the amplified pulse.

Main Results:

• Tunable picosecond pulses with a narrow spectral linewidth of 9.4 pm were generated.
• Pulse duration was measured to be 60 ps.
• Frequency-doubled pulses with 0.5 mJ energy and no background emission were achieved.

Conclusions:

• The developed laser system successfully produces tunable, narrow-linewidth picosecond pulses.
• The laser's characteristics are suitable for sensitive analytical techniques like supersonic jet/resonance-enhanced multiphoton ionization/mass spectrometry.
• This laser system offers a potential advantage for the analysis of challenging analytes such as dioxins.