Laser-plasma coupling for enhanced ablation of GaAs with combined femtosecond and nanosecond pulses
Abstract
The laser-plasma interactions that occur during the ablation of solid materials by a femtosecond filament superimposed with a lower-intensity nanosecond pulse are investigated. Pulses of 50 fs duration with intensities of ∼1014 W/cm2 centered at 800 nm are combined with 8 ns pulses at 1064 nm with ∼1010 W/cm2 intensity with delays of ±40 ns on crystalline GaAs targets in air. For each delay, the volume of material removed by a single femtosecond-nanosecond dual-pulse is compared to the laser-plasma interactions that are captured with ultrafast shadowgraph imaging of the plasma and shockwave generated by each pulse. Sedov-Taylor analysis of the shockwaves provides insight on the coupling of energy from the second pulse to the plasma. These dynamics are corroborated with radiation-hydrodynamics simulations. The interaction of the secondary pulse with the pre-existent plasma is shown to play a critical role in enhancing the material removal.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 01, 2021
- Source ID
- 10.1364/oe.420599
Entities
People
- Haley Kerrigan
- Majid Masnavi
- Martin Richardson
- Robert Bernath
- Shermineh Rostami Fairchild
Organizations
- Air Force Office of Scientific Research
- Army Research Office
- University of Central Florida
- Valencia College