Optical emission enhancement using laser ablation combined with fast pulse discharge

Area of Science:

• Physics
• Materials Science
• Analytical Chemistry

Background:

• Laser ablation is a technique used for material analysis.
• Optical emission from laser-induced plasma can be weak and unstable.
• Improving signal intensity and stability is crucial for accurate elemental analysis.

Purpose of the Study:

• To develop and characterize a high-voltage, fast-pulse discharge circuit for enhancing optical emission from silicon.
• To investigate the effect of the discharge circuit on plasma emission characteristics.
• To evaluate the improvement in signal intensity, stability, and signal-to-noise ratio.

Main Methods:

• A high-voltage and fast-pulse discharge circuit was designed and integrated with laser ablation.
• The discharge circuit's characteristics, including voltage and current oscillations, were analyzed.
• Optical emission from laser-ablated silicon in the presence and absence of the discharge was measured and compared.

Main Results:

• The discharge circuit exhibited damping and periodical oscillations with a short period (~0.5 µs).
• The discharge automatically initiated approximately 1 µs after laser ablation.
• Optical emission intensity was enhanced up to 52 times compared to standard laser ablation.
• Improved line stability (relative standard deviation) and signal-to-noise (S/N) ratio were achieved.

Conclusions:

• The combined high-voltage, fast-pulse discharge and laser ablation technique effectively enhances optical emission from silicon.
• The method provides significant improvements in signal intensity, stability, and S/N ratio, comparable to double-pulse laser-induced breakdown spectroscopy (DP-LIBS).
• This approach holds promise for advancing future elemental analysis applications.