The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform

Shinji Yuasa - One of the best experts on this subject based on the ideXlab platform.

M. Y. Yu - One of the best experts on this subject based on the ideXlab platform.

  • very long Distance Propagation of high energy laser pulse in air
    Physics of Plasmas, 2018
    Co-Authors: Wei Yu, M. Y. Yu, Jingwei Wang, S Rykovanov, Jingjing Ju, Shixia Luan, Kun Li
    Abstract:

    Long Distance Propagation of an energetic laser pulse with intensity slightly below that for multi-photon ionization in air is considered analytically, by noting that in the process, it is mainly the peak region of the pulse that interacts with the air molecules. Similar to that of much shorter femtosecond laser pulses of similar intensity, the affected air becomes slightly ionized and self-consistently forms a co-propagating thin and low-density plasma filament along the axis. It is found that a hundred-Joule-level laser pulse with a relatively large spot radius and pulse duration can propagate (also in the form of a self-consistent filament) tens of kilometers through the atmosphere. Such laser Propagation properties should have applications in many areas.Long Distance Propagation of an energetic laser pulse with intensity slightly below that for multi-photon ionization in air is considered analytically, by noting that in the process, it is mainly the peak region of the pulse that interacts with the air molecules. Similar to that of much shorter femtosecond laser pulses of similar intensity, the affected air becomes slightly ionized and self-consistently forms a co-propagating thin and low-density plasma filament along the axis. It is found that a hundred-Joule-level laser pulse with a relatively large spot radius and pulse duration can propagate (also in the form of a self-consistent filament) tens of kilometers through the atmosphere. Such laser Propagation properties should have applications in many areas.

  • Long-Distance Propagation of intense short laser pulse in air
    Physics of Plasmas, 2004
    Co-Authors: Wei Yu, M. Y. Yu, J. Zhang, L. J. Qian, X. Yuan, Peixiang Lu, R. X. Li, Z. M. Sheng, Z. Z. Xu
    Abstract:

    Long-Distance Propagation of intense laser pulse in air is reconsidered analytically by generalizing the analogy between the laser spotsize and the orbit of a classical particle. It is shown that multiphoton ionization introduces unique features to the laser-air interaction, thereby enabling the long-Distance behavior. Several interesting characteristics of the latter are pointed out.

Edward A. Startsev - One of the best experts on this subject based on the ideXlab platform.

  • Simulating the Long-Distance Propagation of Intense Beams in the Paul Trap Simulator Experiment
    Proceedings of the 2005 Particle Accelerator Conference, 2005
    Co-Authors: Erik P. Gilson, M. Chung, R. Majeski, R.c. Davidson, Philip C. Efthimion, Edward A. Startsev
    Abstract:

    The Paul Trap Simulator Experiment (PTSX) makes use of a compact Paul trap configuration with quadrupolar oscillating wall voltages to simulate the Propagation of intense charged particle beams over Distances of many kilometers through magnetic alternating-gradient transport systems. The simulation is possible because of the similarity between the transverse dynamics of particles in the two systems. One-component pure cesium ion plasmas have been trapped that correspond to normalized intensity parameters ŝ < 0.8, where ŝ is the ratio of the square of the on-axis plasma frequency to twice the square of the average transverse focusing frequency. The PTSX device confines the plasma for hundreds of milliseconds, which is equivalent to beam Propagation over tens of kilometers. Results are presented for experiments in which the amplitude of the oscillating wall voltage waveform has been modified as a function of time. Changing the amplitude for an integral number N of half-cycles and then restoring the amplitude to its original value affects the plasma in a manner that is non-monotonic with N.

  • Simulating the long-Distance Propagation of intense beams in the paul trap simulator experiment
    Proceedings of the IEEE Particle Accelerator Conference, 2005
    Co-Authors: Erik P. Gilson, M. Chung, R. Majeski, R.c. Davidson, Philip C. Efthimion, Edward A. Startsev
    Abstract:

    The Paul Trap Simulator Experiment (PTSX) makes use of a compact Paul trap configuration with quadrupolar oscillating wall voltages to simulate the Propagation of intense charged particle beams over Distances of many kilometers through magnetic alternating-gradient transport systems. The simulation is possible because of the similarity between the transverse dynamics of particles in the two systems. One-component pure cesium ion plasmas have been trapped that correspond to normalized intensity parameters (s) over cap < 0.8, where (s) over cap is the ratio of the square of the on-axis plasma frequency to twice the square of the average transverse focusing frequency. The PTSX device confines the plasma for hundreds of milliseconds, which is equivalent to beam Propagation over tens of kilometers. Results are presented for experiments in which the amplitude of the oscillating wall voltage waveform has been modified as a function of time. Changing the amplitude for an integral number N of half-cycles and then restoring the amplitude to its original value affects the plasma in a manner that is non-monotonic with N.

Jingwei Wang - One of the best experts on this subject based on the ideXlab platform.

  • very long Distance Propagation of high energy laser pulse in air
    Physics of Plasmas, 2018
    Co-Authors: Wei Yu, M. Y. Yu, Jingwei Wang, S Rykovanov, Jingjing Ju, Shixia Luan, Kun Li
    Abstract:

    Long Distance Propagation of an energetic laser pulse with intensity slightly below that for multi-photon ionization in air is considered analytically, by noting that in the process, it is mainly the peak region of the pulse that interacts with the air molecules. Similar to that of much shorter femtosecond laser pulses of similar intensity, the affected air becomes slightly ionized and self-consistently forms a co-propagating thin and low-density plasma filament along the axis. It is found that a hundred-Joule-level laser pulse with a relatively large spot radius and pulse duration can propagate (also in the form of a self-consistent filament) tens of kilometers through the atmosphere. Such laser Propagation properties should have applications in many areas.Long Distance Propagation of an energetic laser pulse with intensity slightly below that for multi-photon ionization in air is considered analytically, by noting that in the process, it is mainly the peak region of the pulse that interacts with the air molecules. Similar to that of much shorter femtosecond laser pulses of similar intensity, the affected air becomes slightly ionized and self-consistently forms a co-propagating thin and low-density plasma filament along the axis. It is found that a hundred-Joule-level laser pulse with a relatively large spot radius and pulse duration can propagate (also in the form of a self-consistent filament) tens of kilometers through the atmosphere. Such laser Propagation properties should have applications in many areas.

Jerome V Moloney - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic nonlinear X waves for femtosecond pulse Propagation in water.
    Physical Review Letters, 2004
    Co-Authors: Miroslav Kolesik, Ewan M Wright, Jerome V Moloney
    Abstract:

    : Recent experiments involving femtosecond pulses in water displayed long-Distance Propagation analogous to that reported in air. We verify this phenomenon numerically and show that the Propagation is dynamic as opposed to self-guided. Furthermore, we demonstrate that the Propagation can be interpreted as being due to dynamic nonlinear X waves whose robustness and role in long-Distance Propagation follows from the interplay between nonlinearity and chromatic dispersion.

  • Recurrent femtosecond pulse collapse in air due to plasma generation: numerical results
    Mathematics and Computers in Simulation, 2001
    Co-Authors: Michal Mlejnek, Miroslav Kolesik, Ewan M Wright, Jerome V Moloney
    Abstract:

    In this report we present numerical simulations of nonlinear pulse Propagation in air to elucidate the physical mechanism underlying the experimentally observed long Distance Propagation of filaments. Simulations of the nonlinear Schrodinger equation for the electromagnetic field coupled to the electron plasma generated via multiphoton ionization yield a very dynamic picture of long Distance Propagation in which pulses form, are absorbed, and subsequently are replenished by new pulses, thereby creating the illusion of one pulse, of energy much less than the input, which is self-guided. Moreover, the evolution of the field and plasma display rich spatio-temporal structures with strong gradients, eventually leading to the breakdown of the numerics. Adaptive mesh refinement methods are explored to overcome these difficulties and to address the onset and recurrence of multiple light filaments during the long Distance Propagation of intense femtosecond infrared pulses in air and point out the features which are common to strong turbulence in other physical systems. The space–time collapse events drive the turbulence here, and plasma defocusing, not dissipation, is the dominant mechanism regularizing the collapse.

  • moving focus versus self waveguiding model for long Distance Propagation of femtosecond pulses in air
    IEEE Journal of Quantum Electronics, 1999
    Co-Authors: Michal Mlejnek, Ewan M Wright, Jerome V Moloney
    Abstract:

    Experiments on focused femtosecond pulse Propagation in air in the infrared which can test whether a strict moving-focus model interpretation is applicable were recently analyzed by Lange et al. Using numerical simulations, we show that filament Propagation can be given a consistent interpretation in terms of the dynamic spatial replenishment model. While the moving-focus model cannot explain the persistence of a filament past the linear focus, the self-waveguiding model also presents problems of interpretation.

  • Dynamic spatial replenishment of femtosecond pulses propagating in air
    Optics Letters, 1998
    Co-Authors: Michal Mlejnek, Ewan M Wright, Jerome V Moloney
    Abstract:

    We present numerical simulations of nonlinear pulse Propagation in air whereby an initial pulse is formed, absorbed by plasma generation, and subsequently replenished by power from the trailing edge of the pulse. This process can occur more than once for high-power input pulses and produce the illusion of long-Distance Propagation of one self-guided pulse.