Launching Plasmons in a Two-Dimensional Material Traversed by a Fast Charged Particle

Area of Science:

• Condensed Matter Physics
• Materials Science

Background:

• Charged particle interactions with 2D materials induce polarization and potential.
• Understanding energy and momentum transfer is crucial for material excitation.

Purpose of the Study:

• To compute induced charge density and potential in 2D materials.
• To analyze the dynamics of plasma wave launching and propagation.
• To investigate the behavior of plasmon waves at large distances.

Main Methods:

• Dielectric-response formalism.
• Maxwell stress tensor analysis.
• Conductivity model for terahertz to mid-infrared frequencies.
• Stationary phase analysis.

Main Results:

• Polarization decomposes into conservative (image force) and dissipative parts.
• Dissipative part drives plasma wave launching, determined by the material's Loss function.
• Real-space and time animations show propagating plasma waves.
• Plasmon wave crests become overdamped at large distances.

Conclusions:

• The study provides a comprehensive model for charged particle interactions in 2D materials.
• Dissipative forces are key to exciting plasma oscillations.
• Retardation effects and plasmon-light line hybridization become significant at long wavelengths.