Laser beam zooming and deflection using a nonlinear metamaterial refracting medium

In-process control of the focal spot size and pointing position of a laser as it interacts with a target (beam zooming and deflection) offers the possibility of unprecedented efficiency improvements in a number of applications, such as inertial confinement fusion and laser micromachining. Here is described a system in which the focussing characteristics of a laser beam at one wavelength can be controlled by a lower-intensity beam at another wavelength, via their mutual interaction with a nonlinear metamaterial refracting medium. Such a metamaterial approach permits the optical response of the medium to be tailored according to the wavelengths of interest and time response required in a given application. A metamolecule unit cell design is described in terms of an equivalent circuit based on a pair of LCR (inductance, capacitance, resistance) circuits coupled by a common nonlinear capacitor. The circuit is studied using an analytical approach to obtain an understanding of its properties and design relationships between circuit parameters. Potential realisations of the circuit are discussed.

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Self-Focusing of Hermite-Cosh-Gaussian Laser Beams in Plasma under Density Transition

Advances in Optics ◽

10.1155/2014/942750 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Manzoor Ahmad Wani ◽

Niti Kant

Keyword(s):

Laser Beam ◽

Plasma Density ◽

Focal Spot ◽

Beam Width ◽

Spot Size ◽

Laser Beams ◽

Equation Approach ◽

Focal Spot Size ◽

Self Focusing ◽

Small Spot

Self-focusing of Hermite-Cosh-Gaussian (HChG) laser beam in plasma under density transition has been discussed here. The field distribution in the medium is expressed in terms of beam-width parameters and decentered parameter. The differential equations for the beam-width parameters are established by a parabolic wave equation approach under paraxial approximation. To overcome the defocusing, localized upward plasma density ramp is considered, so that the laser beam is focused on a small spot size. Plasma density ramp plays an important role in reducing the defocusing effect and maintaining the focal spot size up to several Rayleigh lengths. To discuss the nature of self-focusing, the behaviour of beam-width parameters with dimensionless distance of propagation for various values of decentered parameters is examined by numerical estimates. The results are presented graphically and the effect of plasma density ramp and decentered parameter on self-focusing of the beams has been discussed.

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Heavy-ion beam focusing with a wall-stabilized plasma lens

Laser and Particle Beams ◽

10.1017/s0263034600009344 ◽

1995 ◽

Vol 13 (2) ◽

pp. 221-229 ◽

Cited By ~ 6

Author(s):

A. Tauschwitz ◽

E. Boggasch ◽

D.H.H. Hoffmann ◽

J. Jacoby ◽

U. Neuner ◽

...

Keyword(s):

Inertial Confinement Fusion ◽

Focal Spot ◽

Ion Beam ◽

Heavy Ion ◽

Spot Size ◽

High Energy ◽

Experimental Program ◽

Focal Spot Size ◽

Beam Emittance ◽

Beam Focusing

Focusing of heavy-ion beams is an important issue for ion beam-driven inertial confinement fusion. For the experimental program to investigate matter at high energy densities at GSI, the application of a plasma lens has attractive features compared to standard quadrupole lenses. A plasma lens using a wall-stabilized discharge has been systematically investigated and optimized for this purpose. Different lenses were tested in several runs at the GSI linear accelerator UNILAC and at the SIS-synchrotron. A remarkably high accuracy and reproducibility of the focusing were found. The focal spot size was mainly limited by the beam emittance. A summary of experimental results and important limitations of the focal spot size is given.

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Role of laser beam geometry in improving implosion symmetry and performance for indirect-drive inertial confinement fusion

Physics of Plasmas ◽

10.1063/1.1576762 ◽

2003 ◽

Vol 10 (6) ◽

pp. 2429-2432 ◽

Cited By ~ 12

Author(s):

R. E. Turner ◽

P. A. Amendt ◽

O. L. Landen ◽

L. J. Suter ◽

R. J. Wallace ◽

...

Keyword(s):

Laser Beam ◽

Inertial Confinement Fusion ◽

Inertial Confinement ◽

Beam Geometry ◽

Confinement Fusion ◽

Indirect Drive ◽

And Performance

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Laser amplification by electric pulse power

Laser and Particle Beams ◽

10.1017/s0263034606060708 ◽

2006 ◽

Vol 24 (4) ◽

pp. 525-533 ◽

Cited By ~ 6

Author(s):

F. WINTERBERG

Keyword(s):

Laser Beam ◽

Inertial Confinement Fusion ◽

Electric Pulse ◽

Fast Ignition ◽

Pulse Power ◽

Inertial Confinement ◽

Pinch Effect ◽

Laser Amplification ◽

Confinement Fusion ◽

Indirect Drive

It is proposed that it is possible to amplify the energy of a pulsed laser beam by imploding it inside a capillary metallic liner. If imploded with megaampere currents by the pinch effect, implosion velocities up to ∼3 × 108 cm/s can be reached, imploding a few cm long liner with an inner radius of 2 × 10−3 cm in about ∼10−10 s. If the liner radius can be imploded by 30-fold, the laser pulse would in the absence of absorption losses into the linear wall be amplified 1000-fold. Because the amplification is through the conversion from longer to shorter wave lengths, the concept offers the prospect of intense short wave length laser pulses in the far ultraviolet and soft X-ray domain. Apart from the direct drive laser beam compression by the pinch effect, an alternative indirect drive through the conversion of the electric pulse power into soft X-rays is possible as well. The limitations of this concept are the absorption losses into the liner wall, and ways to overcome these losses are presented. The most important application of the proposed laser amplification scheme might be for the fast ignition of various inertial confinement fusion schemes. An integrated fast ignition inertial confinement fusion concept using the indirect drive is also presented.

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Laser and target experiments on KrF GARPUN laser installation at FIAN

Laser and Particle Beams ◽

10.1017/s0263034699171064 ◽

1999 ◽

Vol 17 (1) ◽

pp. 69-88 ◽

Cited By ~ 8

Author(s):

V.D. ZVORYKIN ◽

I.G. LEBO

Keyword(s):

Inertial Confinement Fusion ◽

Focal Spot ◽

Laser Pulses ◽

Inertial Confinement ◽

Power Laser ◽

Spot Diameter ◽

Confinement Fusion ◽

Short Laser Pulses ◽

Focal Spot Diameter ◽

Laser Installation

Multistage, e-beam-pumped, 100 J-class KrF laser installation “GARPUN” is described with the emphases to high-power laser beam control and target irradiation experiments. The ablation pressures in the megabar range were measured and hydrodynamic flow was investigated both experimentally and by numerical simulations for laser intensities up to 5×1012 W/cm2, pulse duration of 100 ns, and focal spot diameter 150 μm. Graphite-diamond phase transformation under laser loading was observed by dynamic and Raman scattering methods. Some approaches to the fast ignition inertial confinement fusion, using the simultaneous amplification of long and short laser pulses in KrF drivers, are considered.

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Laser beam propagation through inertial confinement fusion hohlraum plasmas

Physics of Plasmas ◽

10.1063/1.2515054 ◽

2007 ◽

Vol 14 (5) ◽

pp. 055705 ◽

Cited By ~ 20

Author(s):

D. H. Froula ◽

L. Divol ◽

N. B. Meezan ◽

S. Dixit ◽

P. Neumayer ◽

...

Keyword(s):

Laser Beam ◽

Inertial Confinement Fusion ◽

Beam Propagation ◽

Inertial Confinement ◽

Laser Beam Propagation ◽

Confinement Fusion

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Measurements of the effect of laser beam smoothing on direct-drive inertial-confinement-fusion capsule implosions

Physical Review Letters ◽

10.1103/physrevlett.68.2774 ◽

1992 ◽

Vol 68 (18) ◽

pp. 2774-2777 ◽

Cited By ~ 19

Author(s):

D. K. Bradley ◽

J. A. Delettrez ◽

C. P. Verdon

Keyword(s):

Laser Beam ◽

Inertial Confinement Fusion ◽

Inertial Confinement ◽

Direct Drive ◽

Confinement Fusion

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Analysis of electroless nickel thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086854 ◽

1991 ◽

Vol 49 ◽

pp. 510-511 ◽

Cited By ~ 1

Author(s):

C. W. Price ◽

E. F. Lindsey

Keyword(s):

Thin Films ◽

Inertial Confinement Fusion ◽

Electroless Nickel ◽

Inertial Confinement ◽

Plating Bath ◽

X Ray ◽

Nickel Thin Films ◽

Nickel Deposits ◽

Confinement Fusion ◽

Thickness Measurements

Thickness measurements of thin films are performed by both energy-dispersive x-ray spectroscopy (EDS) and x-ray fluorescence (XRF). XRF can measure thicker films than EDS, and XRF measurements also have somewhat greater precision than EDS measurements. However, small components with curved or irregular shapes that are used for various applications in the the Inertial Confinement Fusion program at LLNL present geometrical problems that are not conducive to XRF analyses but may have only a minimal effect on EDS analyses. This work describes the development of an EDS technique to measure the thickness of electroless nickel deposits on gold substrates. Although elaborate correction techniques have been developed for thin-film measurements by x-ray analysis, the thickness of electroless nickel films can be dependent on the plating bath used. Therefore, standard calibration curves were established by correlating EDS data with thickness measurements that were obtained by contact profilometry.

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