Chapter 23 - Control of the production of highly charged ions in femtosecond laser cluster fragmentation

• Published in: Femtochemistry and Femtobiology pp. 119 - 122
• Main Authors: Zamith, S., Ni, Y., Aseyev, S.A., Springate, E., Vrakking, M.J.J.
• Format: Book Chapter
• Language: English
• Published: Elsevier B.V 2004
• ISBN: 0444516565; 9780444516565
• DOI: 10.1016/B978-044451656-5/50023-2

The interaction of high intensity laser with clusters has been the subject of many theoretical and experimental studies. Remarkable phenomena in this interaction include very efficient coupling of the laser energy in the cluster, the emission of electrons and ions with high kinetic energies, X-ray emission, and nuclear fusion in deuterium clusters. This chapter discusses the implication of recent experiments for the nano-plasma model. In this model, ionization starts at the beginning of the laser pulse and forms overdense plasma. Due to the hydrodynamic pressure (or Coulomb explosion in case of small clusters), the plasma expands and the electron density ne drops, until it reaches 3 times the critical density ncrit when the field inside the cluster reaches a maximum. In other words, the plasma frequency decreases until it becomes resonant with the laser frequency. Heating of the plasma then leads to the formation of very energetic electrons and ions.