Electromagnetically Induced Transparency in the Strongly Relativistic Regime

Area of Science:

• Plasma Physics
• Laser-Plasma Interactions
• Fusion Energy

Background:

• Stable laser transport in overdense plasmas is crucial for inertial confinement fusion and particle acceleration.
• Electromagnetically induced transparency (EIT) was proposed for laser propagation but failed in bounded plasmas.
• Previous studies indicated EIT is not feasible in real-world plasma scenarios.

Purpose of the Study:

• To investigate the occurrence and stability of EIT in bounded, overdense plasmas.
• To explore the influence of relativistic effects on EIT.
• To develop a model explaining EIT criteria and frequency passbands.

Main Methods:

• Particle-in-cell simulations were employed to model laser-plasma interactions.
• A relativistic three-wave coupling model was developed.
• Analysis of EIT criteria and frequency passbands under varying relativistic regimes.

Main Results:

• EIT was demonstrated to occur in strongly relativistic regimes, enabling stable LF laser propagation in bounded plasmas.
• A wide frequency passband for EIT was identified in the strongly relativistic regime.
• The narrow passband in the weakly relativistic regime explains EIT quenching in previous studies.

Conclusions:

• EIT is achievable in bounded, overdense plasmas under strongly relativistic conditions.
• The developed model provides criteria for EIT occurrence and a wide operational frequency passband.
• Relativistic effects are key to overcoming limitations of EIT in bounded plasmas.