45th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Volume 59, Number 8
Monday–Friday, June 2–6, 2014;
Madison, Wisconsin
Session M8: Focus Session: Interatomic Coulombic Decay
8:00 AM–10:00 AM,
Thursday, June 5, 2014
Room: Hall GJ
Chair: Marc Simon, Universite Pierre et Marie Curie
Abstract ID: BAPS.2014.DAMOP.M8.1
Abstract: M8.00001 : ICD and its exploration by short, intense and coherent light pulses
8:00 AM–8:30 AM
Preview Abstract
Abstract
Author:
Lorenz Cederbaum
(University of Heidelberg)
How does a microscopic system like an atom or a small molecule get rid of
the excess electronic energy it has acquired, for instance, by absorbing a
photon? If this microscopic system is isolated, the issue has been much
investigated and the answer to this question is more or less well known. But
what happens if our system has neighbors as is usually the case in nature or
in the laboratory? In a human society, if our stress is large, we would like
to pass it over to our neighbors. Indeed, this is in brief what happens also
to the sufficiently excited microscopic system. A new mechanism of energy
transfer has been theoretically predicted and verified in several exciting
experiments. This mechanism seems to prevail ``everywhere'' from the extreme
quantum system of the He dimer to water and even to quantum dots. The
transfer is ultrafast and typically dominates other relaxation pathways.
To exploit the high intensity of laser radiation, we propose to select
frequencies at which single-photon absorption is of too low energy and two
or more photons are needed to produce states of an atom that can undergo
interatomic Coulombic decay (ICD) with its neighbors. ICD is an extremely
efficient decay mechanism for excited systems which are embedded in
environment. For the Ne2 dimer it is explicitly demonstrated that the
proposed multiphoton absorption scheme is much more efficient than schemes
used until now, which rely on single-photon absorption. Extensive
calculations on Ne2 show how the low-energy ICD electrons and Ne$+$ pairs
are produced for different laser intensities and pulse durations. At higher
intensities the production of Ne$+$ pairs by successive ionization of the
two atoms becomes competitive and the respective emitted electrons interfere
with the ICD electrons. It is also shown that a measurement after a time
delay can be used to determine the contribution of ICD even at high laser
intensity. The study can provide a hint how the energy deposited by a FEL on
one site in a medium can be transferred fast to the surrounding.
Work on ICD can be found on the ICD Bibliography:
http://www.pci.uni-heidelberg.de/tc/usr/icd/ICD.refbase.html
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2014.DAMOP.M8.1