Plasma holograms for ultrahigh-intensity optics

Abstract

International audienceThe manipulation of ultraintense laser beams gets increasingly challenging with growing laser peak power, as the breakdownof conventional optics imposes ever largerbeamdiameters. Using compact plasma-based optical elements to control or even generate such beams1–4 is a promising approach, since plasmas can sustain considerable light intensities.We introduce a new type of plasma optics, called plasma holograms, by initiating plasma expansion on a flat solid target with a holographic prepulse beam focus. A modulated plasma surface then grows out of the target after ionization, which can be used for several picoseconds to diffract and spatially shape ultraintense laser beams. On the basis of this concept, we demonstrate the generation of fork plasma gratings, which we use to induce optical vortices on a femtosecond laser beam as well as its high-order harmonics, at intensities exceeding 1019Wcm-2. These plasma holograms open up a whole new range of possibilities for the manipulation of ultraintense lasers and the generation of structured coherent short-wavelength sources

Generation of Attosecond Light Pulses from Gas and Solid State Media

“…The factor 4γ 2 max relates to the basic underlying mechanism which is Doppler shifted backscattering of light on a relativistic mirror. It should be pointed out here that these very important predictions of the ROM model have been confirmed not only in 1D-PIC simulations [82,130] but also in experiments [89,133]. Subsequent reports derived a more accurate exponent for the power-law (q ≈ 8/3 instead of q ≈ 5/2) and for the actual cut-off frequency ω co ≈ γ 3 max beyond the power-law roll-off [21,132].…”

“…[67,91]. Due to the experimental obstacles mentioned before, the solid surface harmonics as a robust asec source (that can be utilized for further experiments) is still in the development phase and applicability up to now is mainly dedicated to the studies of the ultrafast dynamics of laser-plasma interaction [82][83][84][85][86]. Nevertheless, recent experiments performed in the non-linear XUV regime [54,92] and recent progress in the laser pulse engineering and solid target technology [5,6,[35][36][37]67] verifies the feasibility of using solid surface harmonics in ultrafast XUV spectroscopy and attosecond science.…”

“…This is the main advantage of the solid surface media compared to all other laser-driven XUV sources. The other unique advantage of HOH from solid surfaces is that it provides a metrology tool to investigate ultrafast plasma dynamical processes, which is otherwise inaccessible experimentally [82][83][84][85][86]. Theoretical predictions [83] show that using~5 fs IR laser pulses with intensity on target in the range of I L~1 0 20 W/cm 2 , pulses of duration~200 asec in thẽ 60 eV photon energy range can be generated with conversion efficiency~10 −1 (~10 15 photons/pulse), while the generation of~5 asec pulses in the keV photon energy range can take place with conversion efficiency~10 −4 (~10 11 photons/pulse).…”

Generation and Applications of Extreme-Ultraviolet Vortices

“…Instead of being formed in an underdense plasma, as in Raman scattering, a transient plasma grating can be formed at the surface of a solid target. The use of this concept to generate intense vortex light has been recently demonstrated experimentally [59].…”

“…This has motivated several experimental, theoretical and numerical advances that take advantage of the nonlinear optical properties of plasmas [50][51][52][53][54][55][56][57][58][59][60][61]. The generation and amplification of vortex beams and its harmonics has been a key component of research related to these recent, but truly exciting, developments.…”