Observation of the plasma channel dynamics and Coulomb explosion in the interaction of a high-intensity laser pulse with a He gas jet

Authors

• G.S. Sarkisov, P. N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow, Russia
• V. Yu. Bychenkov, P. N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow, Russia
• V.T. Tikhonchuk, P. N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow, Russia
• Anatoly Maksimchuk, University of MichiganFollow
• Shouyuan Chen, University of Michigan, Ann ArborFollow
• R. Wagner, University of Michigan, Ann Arbor
• G. Mourou, University of Michigan, Ann Arbor
• Donald P. Umstadter, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

12-25-1997

Comments

Published by Interperiodica. JETP-Letters, 66, 828-34 (1997); translated from Pis’ma Zh. Eksp. Teor. Fiz. 66, 787-92 (1997). HREF="http://www.maik.rssi.ru/cgi-bin/journal.pl?name=jetplet&page=main "http://www.maik.rssi.ru/cgi-bin/journal.pl?name=jetplet&page=main Published by Am Inst Physics.

Abstract

We report the first interferometric observations of the dynamics of electron–ion cavitation of relativistically self-focused intense 4 TW, 400 fs laser pulse in a He gas jet. The electron density in a channel 1 mm long and 30 mm in diameter drops by a factor of approximately 10 from the maximum value of ~8x10¹⁹ cm²³. A high radial velocity of the plasma expansion, ~3.8x10⁸ cm/s, corresponding to an ion energy of about 300 keV, is observed. The total energy of fast ions is estimated to be 6% of the laser pulse energy. The high-velocity radial plasma expulsion is explained by a charge separation due to the strong ponderomotive force. This experiment demonstrates a new possibility for direct transmission of a significant portion of the energy of a laser pulse to ions.