The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
F. Quéré - One of the best experts on this subject based on the ideXlab platform.
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space time characterization of ultra intense femtosecond Laser Beams
Nature Photonics, 2016Co-Authors: G. Pariente, V. Gallet, A. Borot, O. Gobert, F. QuéréAbstract:Femtosecond Lasers can now deliver ultrahigh intensities at focus, making it possible to induce relativistic motion of charged particles with light and opening the way to new generations of compact particle accelerators and X-ray sources. With diameters of up to tens of centimetres, ultra-intense Laser Beams tend to suffer from spatiotemporal distortions, that is, a spatial dependence of their temporal properties that can dramatically reduce their peak intensities. At present, however, these intense electromagnetic fields are characterized and optimized in space and time separately. Here, we present the first complete spatiotemporal experimental reconstruction of the field E(t,r) for a 100 TW peak-power Laser, and reveal the spatiotemporal distortions that can affect such Beams. This new measurement capability opens the way to in-depth characterization and optimization of ultra-intense Lasers and ultimately to the advanced control of relativistic motion of matter with femtosecond Laser Beams structured in space–time. The complete spatiotemporal characterization of a 100-TW Laser beam highlights distortions that must be taken into account for present and future generations of ultra-intense Lasers.
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Space–time characterization of ultra-intense femtosecond Laser Beams
Nature Photonics, 2016Co-Authors: G. Pariente, V. Gallet, A. Borot, O. Gobert, F. QuéréAbstract:Femtosecond Lasers can now deliver ultrahigh intensities at focus, making it possible to induce relativistic motion of charged particles with light and opening the way to new generations of compact particle accelerators and X-ray sources. With diameters of up to tens of centimetres, ultra-intense Laser Beams tend to suffer from spatiotemporal distortions, that is, a spatial dependence of their temporal properties that can dramatically reduce their peak intensities. At present, however, these intense electromagnetic fields are characterized and optimized in space and time separately. Here, we present the first complete spatiotemporal experimental reconstruction of the field E(t,r) for a 100 TW peak-power Laser, and reveal the spatiotemporal distortions that can affect such Beams. This new measurement capability opens the way to in-depth characterization and optimization of ultra-intense Lasers and ultimately to the advanced control of relativistic motion of matter with femtosecond Laser Beams structured in space–time
R Geiger - One of the best experts on this subject based on the ideXlab platform.
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Accurate trajectory alignment in cold-atom interferometers with separated Laser Beams
Phys.Rev.A, 2020Co-Authors: M Altorio, L A Sidorenkov, A Landragin, R. Gautier, D. Savoie, R GeigerAbstract:Cold-atom interferometers commonly face systematic effects originating from the coupling between the trajectory of the atomic wave packet and the wavefront of the Laser Beams driving the interferometer. Detrimental for the accuracy and the stability of such inertial sensors, these systematics are particularly enhanced in architectures based on spatially separated Laser Beams. Here we analyze the effect of a coupling between the relative alignment of two separated Laser Beams and the trajectory of the atomic wave packet in a four-light-pulse cold-atom gyroscope operated in fountain configuration. We present a method to align the two Laser Beams at the 0.2μrad level and to determine the optimal mean velocity of the atomic wave packet with an accuracy of 0.2mms−1. Such fine tuning constrains the associated gyroscope bias to a level of 1×10−10rads−1. In addition, we reveal this coupling using the point-source interferometry technique by analyzing single-shot time-of-flight fluorescence traces, which allows us to measure large angular misalignments between the interrogation Beams. The alignment method which we present here can be employed in other sensor configurations and is particularly relevant to emerging gravitational wave detector concepts based on cold-atom interferometry.
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atom interferometry with top hat Laser Beams
Applied Physics Letters, 2018Co-Authors: N Mielec, M Altorio, Ranjita Chanu Sapam, D Horville, D Holleville, L A Sidorenkov, A Landragin, R GeigerAbstract:The uniformity of the intensity and the phase of Laser Beams is crucial to high-performance atom interferometers. Inhomogeneities in the Laser intensity profile cause contrast reductions and systematic effects in interferometers operated with atom sources at micro-Kelvin temperatures and detrimental diffraction phase shifts in interferometers using large momentum transfer beam splitters. We report on the implementation of a so-called top-hat Laser beam in a long-interrogation-time cold-atom interferometer to overcome the issue of inhomogeneous Laser intensity encountered when using Gaussian Laser Beams. We characterize the intensity and relative phase profiles of the top-hat beam and demonstrate its gain in atom-optic efficiency over a Gaussian beam, in agreement with numerical simulations. We discuss the application of top-hat Beams to improve the performance of different architectures of atom interferometers.The uniformity of the intensity and the phase of Laser Beams is crucial to high-performance atom interferometers. Inhomogeneities in the Laser intensity profile cause contrast reductions and systematic effects in interferometers operated with atom sources at micro-Kelvin temperatures and detrimental diffraction phase shifts in interferometers using large momentum transfer beam splitters. We report on the implementation of a so-called top-hat Laser beam in a long-interrogation-time cold-atom interferometer to overcome the issue of inhomogeneous Laser intensity encountered when using Gaussian Laser Beams. We characterize the intensity and relative phase profiles of the top-hat beam and demonstrate its gain in atom-optic efficiency over a Gaussian beam, in agreement with numerical simulations. We discuss the application of top-hat Beams to improve the performance of different architectures of atom interferometers.
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Atom Interferometry with Top-Hat Laser Beams
Appl.Phys.Lett., 2018Co-Authors: N Mielec, M Altorio, Ranjita Chanu Sapam, D Horville, D Holleville, L A Sidorenkov, A Landragin, R GeigerAbstract:The uniformity of the intensity and the phase of Laser Beams is crucial to high-performance atom interferometers. Inhomogeneities in the Laser intensity profile cause contrast reductions and systematic effects in interferometers operated with atom sources at micro-Kelvin temperatures and detrimental diffraction phase shifts in interferometers using large momentum transfer beam splitters. We report on the implementation of a so-called top-hat Laser beam in a long-interrogation-time cold-atom interferometer to overcome the issue of inhomogeneous Laser intensity encountered when using Gaussian Laser Beams. We characterize the intensity and relative phase profiles of the top-hat beam and demonstrate its gain in atom-optic efficiency over a Gaussian beam, in agreement with numerical simulations. We discuss the application of top-hat Beams to improve the performance of different architectures of atom interferometers.
G. Pariente - One of the best experts on this subject based on the ideXlab platform.
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space time characterization of ultra intense femtosecond Laser Beams
Nature Photonics, 2016Co-Authors: G. Pariente, V. Gallet, A. Borot, O. Gobert, F. QuéréAbstract:Femtosecond Lasers can now deliver ultrahigh intensities at focus, making it possible to induce relativistic motion of charged particles with light and opening the way to new generations of compact particle accelerators and X-ray sources. With diameters of up to tens of centimetres, ultra-intense Laser Beams tend to suffer from spatiotemporal distortions, that is, a spatial dependence of their temporal properties that can dramatically reduce their peak intensities. At present, however, these intense electromagnetic fields are characterized and optimized in space and time separately. Here, we present the first complete spatiotemporal experimental reconstruction of the field E(t,r) for a 100 TW peak-power Laser, and reveal the spatiotemporal distortions that can affect such Beams. This new measurement capability opens the way to in-depth characterization and optimization of ultra-intense Lasers and ultimately to the advanced control of relativistic motion of matter with femtosecond Laser Beams structured in space–time. The complete spatiotemporal characterization of a 100-TW Laser beam highlights distortions that must be taken into account for present and future generations of ultra-intense Lasers.
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Space–time characterization of ultra-intense femtosecond Laser Beams
Nature Photonics, 2016Co-Authors: G. Pariente, V. Gallet, A. Borot, O. Gobert, F. QuéréAbstract:Femtosecond Lasers can now deliver ultrahigh intensities at focus, making it possible to induce relativistic motion of charged particles with light and opening the way to new generations of compact particle accelerators and X-ray sources. With diameters of up to tens of centimetres, ultra-intense Laser Beams tend to suffer from spatiotemporal distortions, that is, a spatial dependence of their temporal properties that can dramatically reduce their peak intensities. At present, however, these intense electromagnetic fields are characterized and optimized in space and time separately. Here, we present the first complete spatiotemporal experimental reconstruction of the field E(t,r) for a 100 TW peak-power Laser, and reveal the spatiotemporal distortions that can affect such Beams. This new measurement capability opens the way to in-depth characterization and optimization of ultra-intense Lasers and ultimately to the advanced control of relativistic motion of matter with femtosecond Laser Beams structured in space–time
H P Mercure - One of the best experts on this subject based on the ideXlab platform.
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filamentation of ultrashort pulse Laser Beams resulting from their propagation over long distances in air
Physics of Plasmas, 1999Co-Authors: B La Fontaine, F Vidal, Z Jiang, C Y Chien, D Comtois, A Desparois, T W Johnston, J C Kieffer, H Pepin, H P MercureAbstract:The propagation of high-power short-pulse Laser Beams over considerable distances in air is studied both experimentally and via numerical simulations. Filaments are formed after 5–10 m and their propagation over distances in excess of 200 m is reported for the first time. The lateral dimensions of the filaments are found to range from about 100 μm to a few millimeters in diameter. The early values of plasma electron density have been inferred to be a few times 1016 cm−3 using longitudinal spectral interferometry. For 500 fs pulses and a wavelength of 1053 nm, the energy in the filament can be quite high initially (∼8 mJ) and is found to stabilize at about 1.5–2 mJ, after about 35 m. A simple model based on the nonlinear Schrodinger equation coupled to a multiphoton ionization law appears to describe several experimental results quite well.The propagation of high-power short-pulse Laser Beams over considerable distances in air is studied both experimentally and via numerical simulations. Filaments are formed after 5–10 m and their propagation over distances in excess of 200 m is reported for the first time. The lateral dimensions of the filaments are found to range from about 100 μm to a few millimeters in diameter. The early values of plasma electron density have been inferred to be a few times 1016 cm−3 using longitudinal spectral interferometry. For 500 fs pulses and a wavelength of 1053 nm, the energy in the filament can be quite high initially (∼8 mJ) and is found to stabilize at about 1.5–2 mJ, after about 35 m. A simple model based on the nonlinear Schrodinger equation coupled to a multiphoton ionization law appears to describe several experimental results quite well.
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filamentation of ultrashort pulse Laser Beams resulting from their propagation over long distances in air
Physics of Plasmas, 1999Co-Authors: B La Fontaine, F Vidal, Z Jiang, C Y Chien, D Comtois, A Desparois, T W Johnston, J C Kieffer, H Pepin, H P MercureAbstract:The propagation of high-power short-pulse Laser Beams over considerable distances in air is studied both experimentally and via numerical simulations. Filaments are formed after 5–10 m and their propagation over distances in excess of 200 m is reported for the first time. The lateral dimensions of the filaments are found to range from about 100 μm to a few millimeters in diameter. The early values of plasma electron density have been inferred to be a few times 1016 cm−3 using longitudinal spectral interferometry. For 500 fs pulses and a wavelength of 1053 nm, the energy in the filament can be quite high initially (∼8 mJ) and is found to stabilize at about 1.5–2 mJ, after about 35 m. A simple model based on the nonlinear Schrodinger equation coupled to a multiphoton ionization law appears to describe several experimental results quite well.
A. Borot - One of the best experts on this subject based on the ideXlab platform.
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space time characterization of ultra intense femtosecond Laser Beams
Nature Photonics, 2016Co-Authors: G. Pariente, V. Gallet, A. Borot, O. Gobert, F. QuéréAbstract:Femtosecond Lasers can now deliver ultrahigh intensities at focus, making it possible to induce relativistic motion of charged particles with light and opening the way to new generations of compact particle accelerators and X-ray sources. With diameters of up to tens of centimetres, ultra-intense Laser Beams tend to suffer from spatiotemporal distortions, that is, a spatial dependence of their temporal properties that can dramatically reduce their peak intensities. At present, however, these intense electromagnetic fields are characterized and optimized in space and time separately. Here, we present the first complete spatiotemporal experimental reconstruction of the field E(t,r) for a 100 TW peak-power Laser, and reveal the spatiotemporal distortions that can affect such Beams. This new measurement capability opens the way to in-depth characterization and optimization of ultra-intense Lasers and ultimately to the advanced control of relativistic motion of matter with femtosecond Laser Beams structured in space–time. The complete spatiotemporal characterization of a 100-TW Laser beam highlights distortions that must be taken into account for present and future generations of ultra-intense Lasers.
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Space–time characterization of ultra-intense femtosecond Laser Beams
Nature Photonics, 2016Co-Authors: G. Pariente, V. Gallet, A. Borot, O. Gobert, F. QuéréAbstract:Femtosecond Lasers can now deliver ultrahigh intensities at focus, making it possible to induce relativistic motion of charged particles with light and opening the way to new generations of compact particle accelerators and X-ray sources. With diameters of up to tens of centimetres, ultra-intense Laser Beams tend to suffer from spatiotemporal distortions, that is, a spatial dependence of their temporal properties that can dramatically reduce their peak intensities. At present, however, these intense electromagnetic fields are characterized and optimized in space and time separately. Here, we present the first complete spatiotemporal experimental reconstruction of the field E(t,r) for a 100 TW peak-power Laser, and reveal the spatiotemporal distortions that can affect such Beams. This new measurement capability opens the way to in-depth characterization and optimization of ultra-intense Lasers and ultimately to the advanced control of relativistic motion of matter with femtosecond Laser Beams structured in space–time
