Plasma-particle interactions in a laser-induced plasma: implications for laser-induced breakdown spectroscopy

Area of Science:

• Plasma physics
• Laser-material interactions
• Atomic spectroscopy

Background:

• The behavior of individual particles within laser-induced plasmas is crucial for applications like single-particle spectroscopy and materials synthesis.
• Understanding particle dissociation, atomic diffusion, and emission dynamics is key to controlling plasma processes.

Purpose of the Study:

• To quantitatively investigate the interaction between laser-induced plasmas and individual particles.
• To determine the time scales of particle dissociation and atomic diffusion.
• To analyze atomic emission characteristics using both imaging and spectroscopic methods.

Main Methods:

• Quantitative plasma imaging studies were employed to observe particle dissociation.
• Nd:YAG laser pulses (300 mJ) were used to generate plasmas.
• Localized atomic emission from calcium atoms was measured to assess spatial nonhomogeneity and diffusion rates.
• Image analysis and traditional spectroscopic techniques were used to analyze atomic emission.

Main Results:

• Individual particles were observed to dissociate within tens of microseconds in the laser-induced plasma.
• Significant spatial nonhomogeneity in atomic emission persisted on a similar time scale.
• An average atomic diffusion rate of 0.04 m^2/s was determined for calcium atoms.
• Both image analysis and spectroscopic methods provided insights into the resulting calcium atomic emission.

Conclusions:

• The study quantifies the rapid dissociation of particles in laser-induced plasmas.
• It establishes a link between particle dissociation, atomic diffusion, and spatial emission patterns.
• The findings have implications for optimizing laser-plasma interactions in spectroscopy and materials synthesis.