Dynamic Control of the Polarization of Intense Laser Beams via Optical Wave Mixing in Plasmas

Abstract

When intense laser beams overlap in plasmas, the refractive index modulation created by the beat wave via the ponderomotive force can lead to optical wave mixing phenomena similar to those used in crystals and photorefractive materials. A new comprehensive analytical description of the modification of the polarization state of laser beams crossing at arbitrary angles in a plasma is presented. It is shown that a laser-plasma system can be used to provide full control of the polarization state of a separate "probe" laser beam; simple analytical estimates and practical considerations are provided for the design of novel photonics devices such as laser-plasma polarizers and wave plates.

Reducing parametric backscattering by polarization rotation

“…On the laser side, multiple manipulation * ibarth@princeton.edu techniques of the incident laser are used to mitigate PB including smoothing methods as spatial smoothing [10], spectral dispersion [11], polarization smoothing [12,13], and a combination of these three smoothing methods [8,9]. Interestingly, perpendicular polarizations can also mitigate cross beam energy transfer, and thereby affect symmetry [14]. Other methods to reduce PB comprise modulation of the laser intensity such that the effective interaction length is reduced, thereby, diminishing the effective growth rate and the reflectivity.…”

Refractive Index Seen by a Probe Beam Interacting with a Laser-Plasma System

“…There has been a recent surge of interest in using laserplasma optical systems to manipulate the basic properties of light waves [1][2][3][4]. Plasma-based photonic devices are attractive because they can be ultrafast, damageresistant, and easily tunable.…”

High Power Dynamic Polarization Control Using Plasma Photonics

“…1a). Using a Jones analysis, we recently showed theoretically [12] that the refractive index modification was only experienced by the "E 1 " component of the probe's electric field parallel to the projection of E 0 in the probe's plane of polarization (cf. Fig.…”

“…The [pump+plasma] optical system seen by the probe is thus birefringent. The full expression for the refractive index perturbation δη was derived in Michel et al [12] using a kinetic plasma model; using a fluid approximation for the plasma, the phase retardation ∆φ = δηk 1 L between the probe's electric field components along the slow and fast axes is given by the simple formula:…”

“…Examples of plasma-based optical components include: plasma mirrors [5], which can be used to redirect, focus, and improve the contrast of laser beams; plasma gratings, which are routinely used at the National Ignition Facility to tune the implosion symmetry of ICF targets by facilitating power transfer between intense lasers [6][7][8]; laser amplifiers [9,10]; and laser compressors [11]. More recently, we showed theoretically that plasmas could also be used to dynamically control the polarization of light waves [12]. In this Letter, we present the first experimental demonstration of a high power, tunable, ultrafast plasma waveplate.…”