Temporal Characterization of a Self-Modulated Laser Wakefield

Authors

• S.P. Le Blanc, University of Michigan, Ann Arbor
• M.C. Downer, University of Michigan, Ann Arbor
• R. Wagner, University of Michigan, Ann Arbor
• Shouyuan Chen, University of Michigan, Ann ArborFollow
• Anatoly Maksimchuk, University of MichiganFollow
• G. Mourou, University of Michigan, Ann Arbor
• Donald P. Umstadter, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

12-30-1996

Comments

Published by American Physical Society. Physical Review Letters 77, 5381 (1996). http://prl.aps.org. Copyright © 1996 American Physical Society. Permission to use.

Abstract

The temporal envelope of plasma density oscillations in the wake of an intense (l∼4×10¹⁸ W/cm², λ = 1 μm) laser pulse (400 fs) is measured using forward Thomson scattering from a copropagating, frequency-doubled probe pulse. The wakefield oscillations in a fully ionized helium plasma (n_e = 3×10¹⁹ cm^-3) are observed to reach maximum amplitude ( δn_e/n_e∼0.1) 300 fs after the pump pulse. The wakefield growth ( 3.5 ps^-1) and decay ( 1.9 ps^-1) rates are consistent with the forward Raman scattering instability and Landau damping, respectively.