Electric field vector measurements via nanosecond electric-field-induced second-harmonic generation

Area of Science:

• Plasma Physics
• Nonlinear Optics
• Laser Spectroscopy

Background:

• Electric-field-induced second-harmonic generation (E-FISH) is a valuable diagnostic technique for electric fields in plasmas.
• Traditional E-FISH methods often require ultrashort laser pulses, limiting their accessibility.

Purpose of the Study:

• To demonstrate the efficacy of E-FISH in the nanosecond regime for plasma diagnostics.
• To enhance the time resolution of E-FISH measurements for non-equilibrium plasma applications.
• To showcase simultaneous measurement of electric field vector components.

Main Methods:

• Utilized nanosecond laser pulses (16 ns) for E-FISH measurements at atmospheric pressure.
• Implemented a Pockels-cell-based pulse-slicing scheme to improve temporal resolution.
• Leveraged the field vector sensitivity of E-FISH signals.

Main Results:

• Achieved field sensitivities of approximately 1 kV/cm with nanosecond pulses.
• Demonstrated a time resolution of ~3 ns using the pulse-slicing technique without compromising signal sensitivity.
• Successfully performed simultaneous measurements of horizontal and vertical electric field components.

Conclusions:

• E-FISH is effective in the nanosecond regime, broadening its applicability with conventional nanosecond lasers.
• The Pockels-cell pulse-slicing scheme offers a cost-effective method for high-time-resolution plasma electric field measurements.
• The ability to measure electric field vector components enhances E-FISH's utility in complex plasma environments.