Matter in ultrastrong laser fields

Luther‐Davies, Barry; Gamalii, E. G.; Wang, Y; Rodé, A. V.; Tikhonchuk, V. T.

doi:10.1070/qe1992v022n04abeh003433

Cited by 56 publications

(28 citation statements)

References 118 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dark solitons have been proposed in the development of optical switching devices (Luther-Davies et al 1992). Here, materials with high nonlinearities are used to reduce the power for soliton formation and the switching threshold; however, an enhanced TPA coefficient also accompanies these materials.…”

Section: Two-photon Absorptionmentioning

confidence: 99%

Perturbations of dark solitons

et al. 2011

View full text Add to dashboard Cite

A direct perturbation method for approximating dark soliton solutions of the nonlinear Schrödinger (NLS) equation under the influence of perturbations is presented. The problem is broken into an inner region, where the core of the soliton resides, and an outer region, which evolves independently of the soliton. It is shown that a shelf develops around the soliton that propagates with speed determined by the background intensity. Integral relations obtained from the conservation laws of the NLS equation are used to determine the properties of the shelf. The analysis is developed for both constant and slowly evolving backgrounds. A number of problems are investigated, including linear and nonlinear damping type perturbations. Keywords: perturbation theory; solitons; opticsPerturbation theory as applied to solitons that decay at infinity, i.e. so-called bright solitons, has been developed over many years (cf. Karpman & Maslov 1977;Kodama & Ablowitz 1981;Herman 1990). The analytical work employs a diverse set of methods including perturbations of the inverse scattering transform (IST), multi-scale perturbation analysis, perturbations of conserved quantities, etc.; the analysis applies to a wide range of physical problems. In optics, a central equation that describes the envelope of a quasi-monochromatic wave train is the nonlinear Schrödinger (NLS) equation, which in normalized form readswhere D, n are constants. In this paper, we consider the NLS equation in a typical nonlinear optics context, where D corresponds to the group-velocity dispersion (GVD), n > 0 is related to the nonlinear index of refraction, z is the

show abstract

Section: Two-photon Absorptionmentioning

confidence: 99%

Perturbations of dark solitons

et al. 2011

View full text Add to dashboard Cite

show abstract

“…On the other hand, MPI is relatively improbable for oxygen atoms or molecules in the ground state [O(2s 2 2p 4 3 P 2 ) and O 2 (X 3 − g )], since their high IPs (13.618 eV and 12.070 eV, respectively) mean that 117 photons and 104 photons (λ = 10.591 µm), respectively, are required for these processes. The probability of MPI W MPI , by absorbing simultaneously n laser photons to strip off an electron, is expressed by the classical formula [37,38] …”

Section: Optical Breakdown Threshold Intensities For Omentioning

confidence: 99%

Optical emission spectroscopy of oxygen plasma induced by IR CO₂pulsed laser

Camacho

Santos

Díaz

et al. 2008

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Laser-induced breakdown (LIB) spectroscopy in oxygen at room temperature and pressures ranging from 4.6 to 75 kPa was studied using a high-power transverse excitation atmospheric CO 2 laser (λ = 9.621 and 10.591 µm; τ FWHM = 64 ns; power densities ranging from 0.87 to 6.31 GW cm −2 ). The spectrum of the generated plasma is dominated by emission of strong O, O + and weak O 2+ atomic lines. Excitation temperatures of 31 500 ± 1600 K and 23 000 ± 3000 K were estimated by means of O 2+ and O + ionic lines, respectively. Electron number densities of the order of (3.5-16.5) × 10 16 cm −3 were deduced from the Stark broadening of several ionic O + lines. The characteristics of the spectral emission intensities from different species have been investigated as functions of the oxygen pressure and laser irradiance. Optical breakdown threshold intensities in O 2 at 10.591 µm have been determined. The physical processes leading to LIB of oxygen have been analysed.

show abstract

“…low ionization probability for λ 2 = 843 nm radiation. The multiphoton ionization rate is given by [43][44][45][46] …”

Section: Plasma Generation Modelmentioning

confidence: 99%

Mechanism and computational model for Lyman-α-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

et al. 2011

View full text Add to dashboard Cite

We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-α (Ly-α) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-α generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-α radiation generation can achieve a value of ∼5×10 −4 which is restricted by the total combined absorption of the fundamental and generated radiation.

show abstract

Matter in ultrastrong laser fields

Cited by 56 publications

References 118 publications

Perturbations of dark solitons

Perturbations of dark solitons

Optical emission spectroscopy of oxygen plasma induced by IR CO₂pulsed laser

Mechanism and computational model for Lyman-α-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

Contact Info

Product

Resources

About

Matter in ultrastrong laser fields

Cited by 56 publications

References 118 publications

Perturbations of dark solitons

Perturbations of dark solitons

Optical emission spectroscopy of oxygen plasma induced by IR CO2pulsed laser

Mechanism and computational model for Lyman-α-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

Contact Info

Product

Resources

About

Optical emission spectroscopy of oxygen plasma induced by IR CO₂pulsed laser