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arXiv · 1007.3237

Observation of a Long-Wavelength Hosing Modulation of a High-Intensity Laser Pulse in Underdense Plasma

M. C. Kaluza·S. P. D. Mangles·A. G. R. Thomas·Z. Najmudin·A. E. Dangor·C. D. Murphy·J. L. Collier·E. J. Divall·P. S. Foster·C. J. Hooker·A. J. Langley·J. Smith·K. Krushelnick
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Abstract

We report the first experimental observation of a long-wavelength hosing modulation of a high-intensity laser pulse. Side-view images of the scattered optical radiation at the fundamental wave-length of the laser reveal a transverse oscillation of the laser pulse during its propagation through underdense plasma. The wavelength of the oscillation λ_hosing depends on the background plasma density n_e and scales as λ_hosing~n_e^-3/2. Comparisons with an analytical model and 2-dimensional particle-in-cell simulations reveal that this laser hosing can be induced by a spatio-temporal asymmetry of the intensity distribution in the laser focus which can be caused by a misalignment of the parabolic focussing mirror or of the diffraction gratings in the pulse compressor.

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M. C. Kaluza, S. P. D. Mangles, A. G. R. Thomas, Z. Najmudin, A. E. Dangor, C. D. Murphy, J. L. Collier, E. J. Divall, P. S. Foster, C. J. Hooker, A. J. Langley, J. Smith, K. Krushelnick. 2010-07-19. Observation of a Long-Wavelength Hosing Modulation of a High-Intensity Laser Pulse in Underdense Plasma. https://doi.org/10.1103/physrevlett.105.095003

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