The Experts below are selected from a list of 33285 Experts worldwide ranked by ideXlab platform
Alexander Pukhov - One of the best experts on this subject based on the ideXlab platform.
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Theory of high-order Harmonic generation in relativistic laser interaction with overdense plasma.
2006Co-Authors: T Baeva, S. Gordienko, Alexander PukhovAbstract:High-order Harmonic generation due to the interaction of a short ultrarelativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultrarelativistic similarity theory we show that the high-order Harmonic Spectrum is universal, i.e., it does not depend on the interaction details. The Spectrum includes the power-law part In proportional variantion for n(-8/3) for n < sqrt of 8 alpha gammamax3, followed by exponential decay. Here gammamax is the largest relativistic gamma factor of the plasma surface and alpha is the second derivative of the surface velocity at this moment. The high-order Harmonic cutoff at proportional variantion gammamax3 is parametrically larger than the 4gammamax2 predicted by the simple "oscillating mirror" model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic gamma factor of the plasma surface. These spikes define the high-order Harmonic Spectrum and lead to attosecond pulses in the reflected radiation.
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theory of high order Harmonic generation in relativistic laser interaction with overdense plasma
2006Co-Authors: T Baeva, S. Gordienko, Alexander PukhovAbstract:High-order Harmonic generation due to the interaction of a short ultrarelativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultrarelativistic similarity theory we show that the high-order Harmonic Spectrum is universal, i.e., it does not depend on the interaction details. The Spectrum includes the power-law part ${I}_{n}\ensuremath{\propto}{n}^{\ensuremath{-}8∕3}$ for $nl\sqrt{8\ensuremath{\alpha}}{\ensuremath{\gamma}}_{\mathrm{max}}^{3}$, followed by exponential decay. Here ${\ensuremath{\gamma}}_{\mathrm{max}}$ is the largest relativistic $\ensuremath{\gamma}$ factor of the plasma surface and $\ensuremath{\alpha}$ is the second derivative of the surface velocity at this moment. The high-order Harmonic cutoff at $\ensuremath{\propto}{\ensuremath{\gamma}}_{\mathrm{max}}^{3}$ is parametrically larger than the $4{\ensuremath{\gamma}}_{\mathrm{max}}^{2}$ predicted by the simple ``oscillating mirror'' model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic $\ensuremath{\gamma}$ factor of the plasma surface. These spikes define the high-order Harmonic Spectrum and lead to attosecond pulses in the reflected radiation.
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relativistic doppler effect universal spectra and zeptosecond pulses
2004Co-Authors: Alexander Pukhov, S. Gordienko, O Shorokhov, T BaevaAbstract:We report on a numerical observation of the train of zeptosecond pulses produced by the reflection of a relativistically intense femtosecond laser pulse from the oscillating boundary of an overdense plasma because of the Doppler effect. These pulses promise to become unique experimental and technological tools since their length is of the order of the Bohr radius and the intensity is extremely high $\ensuremath{\propto}{10}^{19}\text{ }\text{ }\mathrm{W}/{\mathrm{c}\mathrm{m}}^{2}$. We present the physical mechanism, analytical theory, and direct particle-in-cell simulations. We show that the Harmonic Spectrum is universal: the intensity of $n$th Harmonic scales as $1/{n}^{p}$ for $nl4{\ensuremath{\gamma}}^{2}$, where $\ensuremath{\gamma}$ is the largest $\ensuremath{\gamma}$ factor of the electron fluid boundary, and $p=3$ and $p=5/2$ for the broadband and quasimonochromatic laser pulses, respectively.
T Baeva - One of the best experts on this subject based on the ideXlab platform.
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Theory of high-order Harmonic generation in relativistic laser interaction with overdense plasma.
2006Co-Authors: T Baeva, S. Gordienko, Alexander PukhovAbstract:High-order Harmonic generation due to the interaction of a short ultrarelativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultrarelativistic similarity theory we show that the high-order Harmonic Spectrum is universal, i.e., it does not depend on the interaction details. The Spectrum includes the power-law part In proportional variantion for n(-8/3) for n < sqrt of 8 alpha gammamax3, followed by exponential decay. Here gammamax is the largest relativistic gamma factor of the plasma surface and alpha is the second derivative of the surface velocity at this moment. The high-order Harmonic cutoff at proportional variantion gammamax3 is parametrically larger than the 4gammamax2 predicted by the simple "oscillating mirror" model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic gamma factor of the plasma surface. These spikes define the high-order Harmonic Spectrum and lead to attosecond pulses in the reflected radiation.
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theory of high order Harmonic generation in relativistic laser interaction with overdense plasma
2006Co-Authors: T Baeva, S. Gordienko, Alexander PukhovAbstract:High-order Harmonic generation due to the interaction of a short ultrarelativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultrarelativistic similarity theory we show that the high-order Harmonic Spectrum is universal, i.e., it does not depend on the interaction details. The Spectrum includes the power-law part ${I}_{n}\ensuremath{\propto}{n}^{\ensuremath{-}8∕3}$ for $nl\sqrt{8\ensuremath{\alpha}}{\ensuremath{\gamma}}_{\mathrm{max}}^{3}$, followed by exponential decay. Here ${\ensuremath{\gamma}}_{\mathrm{max}}$ is the largest relativistic $\ensuremath{\gamma}$ factor of the plasma surface and $\ensuremath{\alpha}$ is the second derivative of the surface velocity at this moment. The high-order Harmonic cutoff at $\ensuremath{\propto}{\ensuremath{\gamma}}_{\mathrm{max}}^{3}$ is parametrically larger than the $4{\ensuremath{\gamma}}_{\mathrm{max}}^{2}$ predicted by the simple ``oscillating mirror'' model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic $\ensuremath{\gamma}$ factor of the plasma surface. These spikes define the high-order Harmonic Spectrum and lead to attosecond pulses in the reflected radiation.
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relativistic doppler effect universal spectra and zeptosecond pulses
2004Co-Authors: Alexander Pukhov, S. Gordienko, O Shorokhov, T BaevaAbstract:We report on a numerical observation of the train of zeptosecond pulses produced by the reflection of a relativistically intense femtosecond laser pulse from the oscillating boundary of an overdense plasma because of the Doppler effect. These pulses promise to become unique experimental and technological tools since their length is of the order of the Bohr radius and the intensity is extremely high $\ensuremath{\propto}{10}^{19}\text{ }\text{ }\mathrm{W}/{\mathrm{c}\mathrm{m}}^{2}$. We present the physical mechanism, analytical theory, and direct particle-in-cell simulations. We show that the Harmonic Spectrum is universal: the intensity of $n$th Harmonic scales as $1/{n}^{p}$ for $nl4{\ensuremath{\gamma}}^{2}$, where $\ensuremath{\gamma}$ is the largest $\ensuremath{\gamma}$ factor of the electron fluid boundary, and $p=3$ and $p=5/2$ for the broadband and quasimonochromatic laser pulses, respectively.
S. Gordienko - One of the best experts on this subject based on the ideXlab platform.
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Theory of high-order Harmonic generation in relativistic laser interaction with overdense plasma.
2006Co-Authors: T Baeva, S. Gordienko, Alexander PukhovAbstract:High-order Harmonic generation due to the interaction of a short ultrarelativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultrarelativistic similarity theory we show that the high-order Harmonic Spectrum is universal, i.e., it does not depend on the interaction details. The Spectrum includes the power-law part In proportional variantion for n(-8/3) for n < sqrt of 8 alpha gammamax3, followed by exponential decay. Here gammamax is the largest relativistic gamma factor of the plasma surface and alpha is the second derivative of the surface velocity at this moment. The high-order Harmonic cutoff at proportional variantion gammamax3 is parametrically larger than the 4gammamax2 predicted by the simple "oscillating mirror" model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic gamma factor of the plasma surface. These spikes define the high-order Harmonic Spectrum and lead to attosecond pulses in the reflected radiation.
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theory of high order Harmonic generation in relativistic laser interaction with overdense plasma
2006Co-Authors: T Baeva, S. Gordienko, Alexander PukhovAbstract:High-order Harmonic generation due to the interaction of a short ultrarelativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultrarelativistic similarity theory we show that the high-order Harmonic Spectrum is universal, i.e., it does not depend on the interaction details. The Spectrum includes the power-law part ${I}_{n}\ensuremath{\propto}{n}^{\ensuremath{-}8∕3}$ for $nl\sqrt{8\ensuremath{\alpha}}{\ensuremath{\gamma}}_{\mathrm{max}}^{3}$, followed by exponential decay. Here ${\ensuremath{\gamma}}_{\mathrm{max}}$ is the largest relativistic $\ensuremath{\gamma}$ factor of the plasma surface and $\ensuremath{\alpha}$ is the second derivative of the surface velocity at this moment. The high-order Harmonic cutoff at $\ensuremath{\propto}{\ensuremath{\gamma}}_{\mathrm{max}}^{3}$ is parametrically larger than the $4{\ensuremath{\gamma}}_{\mathrm{max}}^{2}$ predicted by the simple ``oscillating mirror'' model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic $\ensuremath{\gamma}$ factor of the plasma surface. These spikes define the high-order Harmonic Spectrum and lead to attosecond pulses in the reflected radiation.
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relativistic doppler effect universal spectra and zeptosecond pulses
2004Co-Authors: Alexander Pukhov, S. Gordienko, O Shorokhov, T BaevaAbstract:We report on a numerical observation of the train of zeptosecond pulses produced by the reflection of a relativistically intense femtosecond laser pulse from the oscillating boundary of an overdense plasma because of the Doppler effect. These pulses promise to become unique experimental and technological tools since their length is of the order of the Bohr radius and the intensity is extremely high $\ensuremath{\propto}{10}^{19}\text{ }\text{ }\mathrm{W}/{\mathrm{c}\mathrm{m}}^{2}$. We present the physical mechanism, analytical theory, and direct particle-in-cell simulations. We show that the Harmonic Spectrum is universal: the intensity of $n$th Harmonic scales as $1/{n}^{p}$ for $nl4{\ensuremath{\gamma}}^{2}$, where $\ensuremath{\gamma}$ is the largest $\ensuremath{\gamma}$ factor of the electron fluid boundary, and $p=3$ and $p=5/2$ for the broadband and quasimonochromatic laser pulses, respectively.
Liu Xueshen - One of the best experts on this subject based on the ideXlab platform.
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single attosecond pulse generation in an orthogonally polarized two color laser field combined with a static electric field
2010Co-Authors: Xia Changlong, Zhang Gangtai, Liu XueshenAbstract:We investigate theoretic high-order Harmonic generation and single attosecond pulse generation in an orthogonally polarized two-color laser field, which is synthesized by a mid-infrared (IR) pulse (12.5 fs, 2000 nm) in the y component and a much weaker (12 fs, 800 nm) pulse in the x component. We find that the width of the Harmonic plateau can be extended when a static electric field is added in the y component. We also investigate emission time of Harmonics in terms of a time-frequency analysis to illustrate the physical mechanism of high-order Harmonic generation. We calculate the ionization rate using the Ammosov-Delone-Krainov model and interpret the variation of Harmonic intensity for different static electric field strengths. When the ratio of strengths of the static and the y-component laser fields is 0.1, a continuous Harmonic Spectrum is formed from 220 to 420 eV. By superposing a properly selected range of the Harmonic Spectrum from 300 to 350 eV, an isolated attosecond pulse with a duration of about 75 as is obtained, which is near linearly polarized.
Armin Scrinzi - One of the best experts on this subject based on the ideXlab platform.
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high Harmonic and single attosecond pulse generation using plasmonic field enhancement in ordered arrays of gold nanoparticles with chirped laser pulses
2013Co-Authors: Yingying Yang, Armin Scrinzi, A Husakou, Sarah L Stebbings, Frederik Susmann, Seungchul Kim, E Ruhl, J Herrmann, Xuechun Lin, Matthias F KlingAbstract:Coherent XUV sources, which may operate at MHz repetition rate, could find applications in high-precision spectroscopy and for spatio-time-resolved measurements of collective electron dynamics on nanostructured surfaces. We theoretically investigate utilizing the enhanced plasmonic fields in an ordered array of gold nanoparticles for the generation of high-Harmonic, extreme-ultraviolet (XUV) radiation. By optimization of the chirp of ultrashort laser pulses incident on the array, our simulations indicate a potential route towards the temporal shaping of the plasmonic near-field and, in turn, the generation of single attosecond pulses. The inherent effects of inhomogeneity of the local fields on the high-Harmonic generation are analyzed and discussed. While taking the inhomogeneity into account does not affect the optimal chirp for the generation of a single attosecond pulse, the cut-off energy of the high-Harmonic Spectrum is enhanced by about a factor of two.
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high Harmonic imaging of few cycle laser pulses
2003Co-Authors: Vladislav S Yakovlev, Armin ScrinziAbstract:We show that the strength of the central electric field peaks in a few-cycle laser pulse can be recovered from a frequency-time image of the high Harmonic Spectrum generated in a gas volume. Pulse intensity, duration, and also the carrier-envelope phase ${\ensuremath{\varphi}}_{\mathrm{C}\mathrm{E}}$ can be determined. A simple and robust observable is defined that provides a gauge of ${\ensuremath{\varphi}}_{\mathrm{C}\mathrm{E}}$ for pulse durations up to three optical cycles, corresponding to 7.8 fs FWHM at the Ti:sapphire wavelength of 800 nm.
