Depolarization of intense laser beams by dynamic plasma density gratings

As a typical plasma-based optical element that can sustain ultra-high light intensity, plasma density gratings driven by intense laser pulses have been extensively studied for wide applications. Here, we show that the plasma density grating driven by two intersecting driver laser pulses is not only nonuniform in space but also varies over time. Consequently, the probe laser pulse that passes through such a dynamic plasma density grating will be depolarized, that is, its polarization becomes spatially and temporally variable. More importantly, the laser depolarization may spontaneously take place for crossed laser beams if their polarization angles are arranged properly. The laser depolarization by a dynamic plasma density grating may find application in mitigating parametric instabilities in laser-driven inertial confinement fusion.

Automated summary

Plasma density gratings driven by intense laser pulses are widely studied for their ability to sustain ultra-high light intensity. This study demonstrates that when driven by two intersecting laser pulses, the plasma density grating becomes spatially and temporally nonuniform, causing depolarization of the probe laser pulse passing through it. Interestingly, laser depolarization can occur spontaneously when crossed laser beams are properly arranged. This finding holds potential for mitigating parametric instabilities in laser-driven inertial confinement fusion.