Identifying Trends in Self-Induced Relativistic Transparency in Plasmas with Ultrafast High Intensity Laser Pulses

A LaserNetUS experiment was conducted at the Scarlet Laser Facility (λ = 800 nm, 35 fs), investigating Relativistic Transparency (RT) in ultrafast high intensity laser plasma interactions. RT is the phenomenon where a high intensity laser heats the electrons in a classically overdense plasma to relativistic energies, so instead of the plasma being opaque to the light, it transmits through the plasma. The targets were 8CB liquid crystal films, with thicknesses varied between 20-200 nm and the laser intensity scanned over the range 10^19-10²¹ W/cm². Transmitted and reflected light were collected via scattering screens, and transmitted temporal and spectral properties were by a GRENOUILLE. We compared the results with 2D particle-in-cell (PIC) OSIRIS 4.0 simulations. We present our findings showing strong trends in transmitted light vs target thickness, as well as an unexpected spatial profile from the transmitted light