Terahertz generation from laser-driven ultrafast current propagation along a wire target

Area of Science:

• Physics
• Plasma Physics
• Electromagnetics

Background:

• Terahertz (THz) radiation has numerous applications.
• Efficient generation of intense, coherent THz radiation remains a challenge.

Purpose of the Study:

• To investigate the generation of intense coherent THz radiation using intense laser pulses obliquely incident on a wire target.
• To explore the underlying physical mechanisms and optimize THz emission.

Main Methods:

• Particle-in-cell (PIC) simulations were employed to model the interaction.
• An analytical model was developed to interpret the simulation results.

Main Results:

• Laser-accelerated fast electrons were confined and guided along the wire surface, acting as a current-carrying antenna.
• A transient current exceeding 10 kA was produced, leading to THz radiation emission.
• The study achieved a laser-to-THz energy conversion efficiency of approximately 0.75%, with a peak electric field of 58 GV/m.

Conclusions:

• The wire target effectively acts as a line antenna for THz radiation generation.
• The developed analytical model accurately reproduces the simulated THz emission characteristics.
• This method offers a promising pathway for efficient THz radiation generation.