Small Metal Clusters in Intense Laser Fields

T. Döppner, S. Teuber, M. Schumacher, J. Tiggesbäumker,
and K.H. Meiwes-Broer

Fachbereich Physik, Universität Rostock, D-18051 Rostock
tiggesbaeumker@.uni-rostock.de

Zusammenfassung:

Neutral metal clusters are exposed to intense femtosecond laser pulses (10¹³-10¹⁶ W/cm²). Atomic fragment distributions were measured for different laser pulse widths. Platinum and lead clusters¹ show an enhanced charging of the atomic fragments for longer pulse widths, e.g., atomic charge states up to z=28 are detected for lead at pulse widths of 1 ps². An enhanced ionization efficiency was also observed by using two 140fs laser pulses having a time delay of 600 fs exciting platinum clusters³. This behavior can be explained^2,3 by simulating the Coulomb explosion of a metallic sphere under tunneling ionization conditions. The calculated time dependent optical response of such a cluster within the framework of the random phase approximation⁴ gives evidence for a multi-plasmon excitation⁵.

 

1. M. Schumacher, S. Teuber, L. Köller, J. Köhn, J. Tiggesbäumker, and K.H. Meiwes-Broer. E.Phys.J.D, 9:411-414, 1999

2. T. Döppner, S. Teuber, M. Schumacher, J. Tiggesbäumker, and K.H. Meiwes-Broer. Appl.Phys.B., submitted

3. L. Köller, M. Schumacher, J. Köhn, S. Teuber, J. Tiggesbäumker, and K.H. Meiwes-Broer. Phys.Rev.Lett., 82:3783-3786, 1999.

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5. P.-G. Reinhard and E. Suraud. E.Phys.J.D., 3:175-178, 1998.