Measurement of Laser Pulse Energy and Duration Through Air Induced Breakdown Under Electric Field Action

This study presents an experimental and analytical investigation of the interactions between laser pulses and air within an electric field generated by a parallel-plate capacitor, which is part of a circuit. This research offers a physical interpretation previously unexplored in the works on this topic. It was found a direct correlation between the measured voltage and the temporal changes in electric flux induced by plasma generated by the laser pulses, and consequently, that the variation of the electric flux is proportional to the time integral of the voltage measured across a resistor of the circuit. The behavior of this last parameter mirrors that of the laser pulse, particularly up to its peak value, which facilitates the determination of its duration. Furthermore, within a specific range, it is feasible to ascertain the incident energy of the laser pulses knowing the maximum value of the electric flux variation. These findings hold significant potential for practical applications in laser pulse diagnostics. Unlike common commercial devices, after a proper calibration, the proposed system can simultaneously determine the energy and duration of laser pulses.