Intense multicycle THz pulse generation from laser-produced nanoplasmas.

Area of Science:

• Plasma Physics
• Laser-Matter Interaction
• Terahertz (THz) Science and Technology

Background:

• Current terahertz (THz) sources from laser-solid interactions primarily produce broadband, single-cycle pulses.
• There is a lack of narrowband THz sources with high field strengths (GV/m-level) suitable for demanding applications.

Purpose of the Study:

• To present a novel scheme for generating robust, narrowband, and tunable THz emission.
• To achieve high-peak field strength THz pulses from laser-plasma interactions.

Main Methods:

• Utilized a nano-dimensional overdense plasma target irradiated by two counter-propagating, detuned laser pulses.
• Employed two- and three-dimensional particle-in-cell simulations to analyze the underlying physics.
• Investigated the generation of strong plasma currents via the beat ponderomotive force.

Main Results:

• Generated intense THz pulses with a peak field strength of 11.9 GV/m.
• Achieved a narrow spectral width ([Formula: see text]), indicating a narrowband THz source.
• Demonstrated a high brightness regime of TW/cm[Formula: see text] for the narrowband THz emission.

Conclusions:

• The proposed scheme successfully produces intense, narrowband THz radiation with unprecedented field strength.
• This novel THz source is highly suitable for various ambitious scientific and technological applications.
• The findings pave the way for developing next-generation THz sources based on laser-plasma interactions.