High order harmonic radiation source for multicolor extreme ultraviolet radiography of carbon plumes

Abstract

Multicolor radiography is used for the characterization of atoms, ions, and molecules of carbon plasma plumes formed by focusing a 200 ps Ti:sapphire laser pulse on a solid graphite target. The radiography of the plume was carried out using a high order harmonic generation based radiation source consisting of the 11th (λ ≈ 72.7 nm) to 21st (λ ≈ 38 nm) odd harmonic orders of the Ti:sapphire laser pulse. The density profile of CI, CII, and carbon dimer molecule (C2) is estimated from the 2D-transmission profile of the harmonics, recorded after passing through the carbon plume. The peak densities of CI, CII, and C2 at a 50 ns delay are estimated to be 8 × 1024 m−3, 4 × 1024 m−3, and 3.5 × 1023 m−3 at distances of 150 μm, 170 μm, and 120 μm away from the target surface, respectively. The expansion speed of the plasma plume front is estimated to be 2 × 104 m/s and the speed of the C2 molecule to be 4 × 103 m/s at a laser intensity of 1011 W cm−2. The present study demonstrates ultrafast multicolor radiography as a simple and versatile tool for a simultaneous estimation of the density profile of neutral atoms, ions, and molecular species of the plasma plume.

Laser-Induced Molecular Plasma: A Medium for High-Order Harmonics Generation of Ultrashort Pulses

“…Laser-induced plasma (LIP) has demonstrated its attractiveness as an advanced medium for harmonics generation. Numerous atomic targets have been used for these purposes [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. Various advanced processes, such as the resonance enhancement of a single harmonic, two-color pump of plasma, quasi-phase-matching and nanoparticle-induced growth of harmonic yield, have been reported, allowing for the formation of sources of coherent XUV radiation.…”

Probing Laser Plasma Dynamics Using High-Order Harmonics Generation in Carbon-Containing Nanomaterials

“…High-order harmonic generation (HHG) in extreme ultraviolet (XUV) range, which occurs when an intense laser pulse interacts with laser-induced plasma (LIP) formed by another laser pulse on the surfaces of bulk targets, is a rich field for a variety of material studies [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. The high-order nonlinear optical properties of various inorganic nanoparticles (Ag, Au, Pd, Pt, Ru, BaTiO 3 , and SrTiO 3 ) appearing in LIP were reviewed in [16].…”

Application of 150 kHz Laser for High-Order Harmonic Generation in Different Plasmas

“…The demonstration of the high flux of harmonics from different plasmas opens doors for further developments in the nonlinear spectroscopy of ablated materials. With the demonstration of highest average flux of harmonics reported so far, one can define the plasma as a very effective medium for coherent XUV sources formation [49][50][51].…”