[Zurück]

E. Gruber, R.A. Wilhelm, R. Heller, R. Ritter, S. Facsko, F. Aumayr:
"Charge state dependent energy loss and charge exchange of slow highly charged ions passing through carbon nano membranes";
Poster: 26th International Conference on Atomic Collisions in Solids (ICACS-26), Debrecen/Hungary; 15.07.2014.

The interaction of slow highly charged ions (HCI) with solid surfaces has been
excessively investigated within the recent past. Especial
ly in the focus of nano structure
creation by HCI impact numerous systematic experiments have been carried out and
revealed in a variety of different models describing e.g. the creation of nano hillocks,
mono atomic deep pits and etch pits on different kin
d of (bulk) materials [1
-
5].
In recent investigations we have put our focus on a new kind of target
-
one
nanometer thin carbon nano sheets. We could show that HCIs can efficiently induce the
creation of nm
-
sized pores in these membranes [6]. However, the
extremely small
thickness of this special target offered us a second opportunity
-
the observation of the
projectile right after the interaction process in terms of its energy loss and charge
exchange. For this purpose we designed an electrostatic analyzer
that allowed us to
determine both quantities experimentally.
The results of those measurements show an unexpected two
-
fold ion charge sate
distribution after passing the membrane comprising (a) ions with very high charge
states (close to the initial one)
that lost nearly no kinetic energy as well as (b) very low
charged ions that lost a significant amount of kinetic energy. The balance of both
contributions was found to be determined by the initial ion charge state. From our
experimental findings we could
draw a microscopic picture of the interaction process
that is presented in the present contribution.