The Experts below are selected from a list of 189 Experts worldwide ranked by ideXlab platform
R S Marjoribanks - One of the best experts on this subject based on the ideXlab platform.
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:The introduction of ultraintense picosecond and sub-picosecond chirped-pulse amplification Lasers has broughta flurry of research interest in developing and usinghigh peak-brightness soft-x-ray and x-ray sources. High-harmonic generation from Laser interaction with noblegases has recently produced presumably coherent softx rays in the “water window” between absorption edgesof carbon and oxygen [1], and analogous generation fromnear-solid-density Laser-produced Plasmas has promise ofmuch more efficient conversion [2]. Such sources showlittle immediate prospect of extension to high-peak-fluxsources of kiloelectron-volt photons, needed, for example,in single-event pulse-probe studies in materials science[3]. Certain tabletop extreme ultraviolet (XUV) andsoft-x-ray Laser schemes require intense picosecond pulsesof keV x-rays as pump sources [4]. Studies in biophysicsand biochemistry which currently use synchrotron orx-ray Laser sources [5] would benefit substantially fromsimpler intense sources in the so-called water window(2.3–4.4 nm). In this context, there is intensified interestin “direct,” efficient, x-ray production from Laser-producedPlasmas, using ultraintense ultrafast optical pulses [6].Intense, short-duration keV x-ray pulse productionin this case depends initially on the optical physics ofinteraction of intense light with near-solid plasma, andsubsequently on the hydrodynamics of the plasma and theredistribution of absorbed energy within the material [7].Specially nanostructured surfaces have been introduced, inan effort effectively to reduce the material surface-currentresponse and the coherent scattering of Laser light fromflat solid surfaces. These surfaces greatly increase the op-tical absorptivity by depositing sootlike clusters of metalatoms (“smoke”), or by creating nanolithographic gratinggrooves in solid surfaces [8,9]; special prepulses have alsobeen used to structure the plasma interaction surface so asto enhance surface-wave coupling, to similar effect [10].Likewise, gas targets consisting of large clusters of noble-gas atoms have recently been investigated [11]. Sincethe efficiency of reradiation of Laser energy as x raysdepends on the profiles of density and temperature withinthe plasma created, these target types have differentconversion efficiencies and characteristic x-ray emissionduration: short-duration pules for nanogroove-gratingtargets, but at moderate conversion efficiency; higherconversion to x rays for smoke targets, but with pulsedurations as long as a hundred picoseconds, and muchlonger for atomic clusters. Particularly, the initial densityof material is a determining factor in the duration of thex-ray pulse, as may be the expansion divergence of theplasma created—initially spherical in the case of smokeclusters, and planar for nanolithographic groove targets.Here we introduce a qualitatively new opticallyanisotropic material useful for targets, intermediate in typeto smoke and nanogroove gratings, with a microscopiccylindrical geometry, and similarly large low-intensityabsorption 95% . This material consists of a surfaceof end-standing 10–200 nm diam metallic fibers, in astructure resembling velvet fabric, which may be cheaplyfabricated from a range of different atomic elementsfrom aluminum to platinum [12]. Individual fibers arenear-solid density, and the overall density of the materialis one-quarter to one-half solid. With an initial densitysimilar to the nanogroove-grating target, and an expansiondivergence intermediate to that of smoke and gratingstructures, these metallic velvets are found to producehigh x-ray energy conversion ( 0.01% for hn.900 eV),similar to smoke targets, but with x-ray pulses of a fewpicosecond, similar to nanogroove-grating targets. In thiscombination, these “velvet” nanostructures produce thebrightest x-ray pulses of the three types.These velvet targets are electrochemically fabricated onAl substrates; their general characteristics and constructionare described in detail elsewhere [12]. Three features ofthe process, attractive for plasma physics experiments, are(1) a wide variety of metals and/or semiconductors can beused; (2) more than one element can be deposited simulta-neously; (3) surfaces of large size and arbitrary shape canbe processed to produce the desired velvet target.0031-9007 00 84(22) 5149(4)$15.00 © 2000 The American Physical Society 5149
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:We describe the optical, radiative, and Laser-plasma physics of a new type of nanostructured surface especially promising as a very high absorption target for high-peak-power subpicosecond Laser-matter interaction. This oriented-nanowire material, irradiated by 1 ps pulses at intensities up to ${10}^{17}\mathrm{W}{\mathrm{cm}}^{\ensuremath{-}2}$, produces picosecond soft x-ray pulses $50\ifmmode\times\else\texttimes\fi{}$ more efficiently than do solid targets. We compare this to ``smoke'' or metallic clusters, and solid nanogroove-grating surfaces; the ``metal-velvet'' targets combine the high yield of smoke targets with the brief emission of grating surfaces.
Martin Richardson - One of the best experts on this subject based on the ideXlab platform.
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ultraviolet out of band radiation studies in Laser tin plasma sources
Journal of Applied Physics, 2017Co-Authors: Homaira Parchamy, John Szilagyi, Majid Masnavi, Martin RichardsonAbstract:Out-of-band long wavelength emission measurements from high power, high-repetition-rate extreme-ultra-violet lithography (EUVL) Laser plasma sources are imperative to estimating heat deposition in EUV mirrors, and the impact of short wavelength light transported through the imaging system to the wafer surface. This paper reports a series of experiments conducted to measure the absolute spectral irradiances of Laser-Plasmas produced from planar tin targets over the wavelength region of 124 to 164 nm by 1.06 μm wavelength, 10 ns full-width-at-half-maximum Gaussian Laser pulses. The use of spherical targets is relevant to the EUVL source scenario. Although Plasmas produced from planar surfaces evolve differently, there is a close similarity to the evolution of current from 10.6 μm CO2 Laser EUVL sources, which use a pre-pulse from a lower energy solid-state Laser to melt and reform an initial spherical droplet into a thin planar disc target. The maximum of radiation conversion efficiency in the 124–164 nm wa...
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spectral irradiance of singly and doubly ionized zinc in low intensity Laser plasma ultraviolet light sources
Journal of Applied Physics, 2017Co-Authors: John Szilagyi, Homaira Parchamy, Majid Masnavi, Martin RichardsonAbstract:The absolute spectral irradiances of Laser-Plasmas produced from planar zinc targets are determined over a wavelength region of 150 to 250 nm. Strong spectral radiation is generated using 60 ns full-width-at-half-maximum, 1.0 μm wavelength Laser pulses with incident Laser intensities as low as ∼5 × 108 W cm−2. A typical radiation conversion efficiency of ∼2%/2πsr is measured. Numerical calculations using a comprehensive radiation-hydrodynamics model reveal the strong experimental spectra to originate mainly from 3d94s4p-3d94s2, 3d94s4d-3d94s4p, and 3d94p-3d94s, 3d94d-3d94p unresolved-transition arrays in singly and doubly ionized zinc, respectively.
G Kulcsar - One of the best experts on this subject based on the ideXlab platform.
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:The introduction of ultraintense picosecond and sub-picosecond chirped-pulse amplification Lasers has broughta flurry of research interest in developing and usinghigh peak-brightness soft-x-ray and x-ray sources. High-harmonic generation from Laser interaction with noblegases has recently produced presumably coherent softx rays in the “water window” between absorption edgesof carbon and oxygen [1], and analogous generation fromnear-solid-density Laser-produced Plasmas has promise ofmuch more efficient conversion [2]. Such sources showlittle immediate prospect of extension to high-peak-fluxsources of kiloelectron-volt photons, needed, for example,in single-event pulse-probe studies in materials science[3]. Certain tabletop extreme ultraviolet (XUV) andsoft-x-ray Laser schemes require intense picosecond pulsesof keV x-rays as pump sources [4]. Studies in biophysicsand biochemistry which currently use synchrotron orx-ray Laser sources [5] would benefit substantially fromsimpler intense sources in the so-called water window(2.3–4.4 nm). In this context, there is intensified interestin “direct,” efficient, x-ray production from Laser-producedPlasmas, using ultraintense ultrafast optical pulses [6].Intense, short-duration keV x-ray pulse productionin this case depends initially on the optical physics ofinteraction of intense light with near-solid plasma, andsubsequently on the hydrodynamics of the plasma and theredistribution of absorbed energy within the material [7].Specially nanostructured surfaces have been introduced, inan effort effectively to reduce the material surface-currentresponse and the coherent scattering of Laser light fromflat solid surfaces. These surfaces greatly increase the op-tical absorptivity by depositing sootlike clusters of metalatoms (“smoke”), or by creating nanolithographic gratinggrooves in solid surfaces [8,9]; special prepulses have alsobeen used to structure the plasma interaction surface so asto enhance surface-wave coupling, to similar effect [10].Likewise, gas targets consisting of large clusters of noble-gas atoms have recently been investigated [11]. Sincethe efficiency of reradiation of Laser energy as x raysdepends on the profiles of density and temperature withinthe plasma created, these target types have differentconversion efficiencies and characteristic x-ray emissionduration: short-duration pules for nanogroove-gratingtargets, but at moderate conversion efficiency; higherconversion to x rays for smoke targets, but with pulsedurations as long as a hundred picoseconds, and muchlonger for atomic clusters. Particularly, the initial densityof material is a determining factor in the duration of thex-ray pulse, as may be the expansion divergence of theplasma created—initially spherical in the case of smokeclusters, and planar for nanolithographic groove targets.Here we introduce a qualitatively new opticallyanisotropic material useful for targets, intermediate in typeto smoke and nanogroove gratings, with a microscopiccylindrical geometry, and similarly large low-intensityabsorption 95% . This material consists of a surfaceof end-standing 10–200 nm diam metallic fibers, in astructure resembling velvet fabric, which may be cheaplyfabricated from a range of different atomic elementsfrom aluminum to platinum [12]. Individual fibers arenear-solid density, and the overall density of the materialis one-quarter to one-half solid. With an initial densitysimilar to the nanogroove-grating target, and an expansiondivergence intermediate to that of smoke and gratingstructures, these metallic velvets are found to producehigh x-ray energy conversion ( 0.01% for hn.900 eV),similar to smoke targets, but with x-ray pulses of a fewpicosecond, similar to nanogroove-grating targets. In thiscombination, these “velvet” nanostructures produce thebrightest x-ray pulses of the three types.These velvet targets are electrochemically fabricated onAl substrates; their general characteristics and constructionare described in detail elsewhere [12]. Three features ofthe process, attractive for plasma physics experiments, are(1) a wide variety of metals and/or semiconductors can beused; (2) more than one element can be deposited simulta-neously; (3) surfaces of large size and arbitrary shape canbe processed to produce the desired velvet target.0031-9007 00 84(22) 5149(4)$15.00 © 2000 The American Physical Society 5149
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:We describe the optical, radiative, and Laser-plasma physics of a new type of nanostructured surface especially promising as a very high absorption target for high-peak-power subpicosecond Laser-matter interaction. This oriented-nanowire material, irradiated by 1 ps pulses at intensities up to ${10}^{17}\mathrm{W}{\mathrm{cm}}^{\ensuremath{-}2}$, produces picosecond soft x-ray pulses $50\ifmmode\times\else\texttimes\fi{}$ more efficiently than do solid targets. We compare this to ``smoke'' or metallic clusters, and solid nanogroove-grating surfaces; the ``metal-velvet'' targets combine the high yield of smoke targets with the brief emission of grating surfaces.
F W Budnik - One of the best experts on this subject based on the ideXlab platform.
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:The introduction of ultraintense picosecond and sub-picosecond chirped-pulse amplification Lasers has broughta flurry of research interest in developing and usinghigh peak-brightness soft-x-ray and x-ray sources. High-harmonic generation from Laser interaction with noblegases has recently produced presumably coherent softx rays in the “water window” between absorption edgesof carbon and oxygen [1], and analogous generation fromnear-solid-density Laser-produced Plasmas has promise ofmuch more efficient conversion [2]. Such sources showlittle immediate prospect of extension to high-peak-fluxsources of kiloelectron-volt photons, needed, for example,in single-event pulse-probe studies in materials science[3]. Certain tabletop extreme ultraviolet (XUV) andsoft-x-ray Laser schemes require intense picosecond pulsesof keV x-rays as pump sources [4]. Studies in biophysicsand biochemistry which currently use synchrotron orx-ray Laser sources [5] would benefit substantially fromsimpler intense sources in the so-called water window(2.3–4.4 nm). In this context, there is intensified interestin “direct,” efficient, x-ray production from Laser-producedPlasmas, using ultraintense ultrafast optical pulses [6].Intense, short-duration keV x-ray pulse productionin this case depends initially on the optical physics ofinteraction of intense light with near-solid plasma, andsubsequently on the hydrodynamics of the plasma and theredistribution of absorbed energy within the material [7].Specially nanostructured surfaces have been introduced, inan effort effectively to reduce the material surface-currentresponse and the coherent scattering of Laser light fromflat solid surfaces. These surfaces greatly increase the op-tical absorptivity by depositing sootlike clusters of metalatoms (“smoke”), or by creating nanolithographic gratinggrooves in solid surfaces [8,9]; special prepulses have alsobeen used to structure the plasma interaction surface so asto enhance surface-wave coupling, to similar effect [10].Likewise, gas targets consisting of large clusters of noble-gas atoms have recently been investigated [11]. Sincethe efficiency of reradiation of Laser energy as x raysdepends on the profiles of density and temperature withinthe plasma created, these target types have differentconversion efficiencies and characteristic x-ray emissionduration: short-duration pules for nanogroove-gratingtargets, but at moderate conversion efficiency; higherconversion to x rays for smoke targets, but with pulsedurations as long as a hundred picoseconds, and muchlonger for atomic clusters. Particularly, the initial densityof material is a determining factor in the duration of thex-ray pulse, as may be the expansion divergence of theplasma created—initially spherical in the case of smokeclusters, and planar for nanolithographic groove targets.Here we introduce a qualitatively new opticallyanisotropic material useful for targets, intermediate in typeto smoke and nanogroove gratings, with a microscopiccylindrical geometry, and similarly large low-intensityabsorption 95% . This material consists of a surfaceof end-standing 10–200 nm diam metallic fibers, in astructure resembling velvet fabric, which may be cheaplyfabricated from a range of different atomic elementsfrom aluminum to platinum [12]. Individual fibers arenear-solid density, and the overall density of the materialis one-quarter to one-half solid. With an initial densitysimilar to the nanogroove-grating target, and an expansiondivergence intermediate to that of smoke and gratingstructures, these metallic velvets are found to producehigh x-ray energy conversion ( 0.01% for hn.900 eV),similar to smoke targets, but with x-ray pulses of a fewpicosecond, similar to nanogroove-grating targets. In thiscombination, these “velvet” nanostructures produce thebrightest x-ray pulses of the three types.These velvet targets are electrochemically fabricated onAl substrates; their general characteristics and constructionare described in detail elsewhere [12]. Three features ofthe process, attractive for plasma physics experiments, are(1) a wide variety of metals and/or semiconductors can beused; (2) more than one element can be deposited simulta-neously; (3) surfaces of large size and arbitrary shape canbe processed to produce the desired velvet target.0031-9007 00 84(22) 5149(4)$15.00 © 2000 The American Physical Society 5149
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:We describe the optical, radiative, and Laser-plasma physics of a new type of nanostructured surface especially promising as a very high absorption target for high-peak-power subpicosecond Laser-matter interaction. This oriented-nanowire material, irradiated by 1 ps pulses at intensities up to ${10}^{17}\mathrm{W}{\mathrm{cm}}^{\ensuremath{-}2}$, produces picosecond soft x-ray pulses $50\ifmmode\times\else\texttimes\fi{}$ more efficiently than do solid targets. We compare this to ``smoke'' or metallic clusters, and solid nanogroove-grating surfaces; the ``metal-velvet'' targets combine the high yield of smoke targets with the brief emission of grating surfaces.
Peter R Herman - One of the best experts on this subject based on the ideXlab platform.
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:The introduction of ultraintense picosecond and sub-picosecond chirped-pulse amplification Lasers has broughta flurry of research interest in developing and usinghigh peak-brightness soft-x-ray and x-ray sources. High-harmonic generation from Laser interaction with noblegases has recently produced presumably coherent softx rays in the “water window” between absorption edgesof carbon and oxygen [1], and analogous generation fromnear-solid-density Laser-produced Plasmas has promise ofmuch more efficient conversion [2]. Such sources showlittle immediate prospect of extension to high-peak-fluxsources of kiloelectron-volt photons, needed, for example,in single-event pulse-probe studies in materials science[3]. Certain tabletop extreme ultraviolet (XUV) andsoft-x-ray Laser schemes require intense picosecond pulsesof keV x-rays as pump sources [4]. Studies in biophysicsand biochemistry which currently use synchrotron orx-ray Laser sources [5] would benefit substantially fromsimpler intense sources in the so-called water window(2.3–4.4 nm). In this context, there is intensified interestin “direct,” efficient, x-ray production from Laser-producedPlasmas, using ultraintense ultrafast optical pulses [6].Intense, short-duration keV x-ray pulse productionin this case depends initially on the optical physics ofinteraction of intense light with near-solid plasma, andsubsequently on the hydrodynamics of the plasma and theredistribution of absorbed energy within the material [7].Specially nanostructured surfaces have been introduced, inan effort effectively to reduce the material surface-currentresponse and the coherent scattering of Laser light fromflat solid surfaces. These surfaces greatly increase the op-tical absorptivity by depositing sootlike clusters of metalatoms (“smoke”), or by creating nanolithographic gratinggrooves in solid surfaces [8,9]; special prepulses have alsobeen used to structure the plasma interaction surface so asto enhance surface-wave coupling, to similar effect [10].Likewise, gas targets consisting of large clusters of noble-gas atoms have recently been investigated [11]. Sincethe efficiency of reradiation of Laser energy as x raysdepends on the profiles of density and temperature withinthe plasma created, these target types have differentconversion efficiencies and characteristic x-ray emissionduration: short-duration pules for nanogroove-gratingtargets, but at moderate conversion efficiency; higherconversion to x rays for smoke targets, but with pulsedurations as long as a hundred picoseconds, and muchlonger for atomic clusters. Particularly, the initial densityof material is a determining factor in the duration of thex-ray pulse, as may be the expansion divergence of theplasma created—initially spherical in the case of smokeclusters, and planar for nanolithographic groove targets.Here we introduce a qualitatively new opticallyanisotropic material useful for targets, intermediate in typeto smoke and nanogroove gratings, with a microscopiccylindrical geometry, and similarly large low-intensityabsorption 95% . This material consists of a surfaceof end-standing 10–200 nm diam metallic fibers, in astructure resembling velvet fabric, which may be cheaplyfabricated from a range of different atomic elementsfrom aluminum to platinum [12]. Individual fibers arenear-solid density, and the overall density of the materialis one-quarter to one-half solid. With an initial densitysimilar to the nanogroove-grating target, and an expansiondivergence intermediate to that of smoke and gratingstructures, these metallic velvets are found to producehigh x-ray energy conversion ( 0.01% for hn.900 eV),similar to smoke targets, but with x-ray pulses of a fewpicosecond, similar to nanogroove-grating targets. In thiscombination, these “velvet” nanostructures produce thebrightest x-ray pulses of the three types.These velvet targets are electrochemically fabricated onAl substrates; their general characteristics and constructionare described in detail elsewhere [12]. Three features ofthe process, attractive for plasma physics experiments, are(1) a wide variety of metals and/or semiconductors can beused; (2) more than one element can be deposited simulta-neously; (3) surfaces of large size and arbitrary shape canbe processed to produce the desired velvet target.0031-9007 00 84(22) 5149(4)$15.00 © 2000 The American Physical Society 5149
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intense picosecond x ray pulses from Laser Plasmas by use of nanostructured velvet targets
Physical Review Letters, 2000Co-Authors: G Kulcsar, D Almawlawi, F W Budnik, Peter R Herman, Martin Moskovits, L Zhao, R S MarjoribanksAbstract:We describe the optical, radiative, and Laser-plasma physics of a new type of nanostructured surface especially promising as a very high absorption target for high-peak-power subpicosecond Laser-matter interaction. This oriented-nanowire material, irradiated by 1 ps pulses at intensities up to ${10}^{17}\mathrm{W}{\mathrm{cm}}^{\ensuremath{-}2}$, produces picosecond soft x-ray pulses $50\ifmmode\times\else\texttimes\fi{}$ more efficiently than do solid targets. We compare this to ``smoke'' or metallic clusters, and solid nanogroove-grating surfaces; the ``metal-velvet'' targets combine the high yield of smoke targets with the brief emission of grating surfaces.
