INVESTIGADORES
MITNIK Dario Marcelo
congresos y reuniones científicas
Título:
Energy loss and mean excitation energy of ions in solids within the shellwise local plasma approximation
Autor/es:
C.C. MONTANARI, D.M. MITNIK, C.D. ARCHUBI AND J.E. MIRAGLIA
Lugar:
Gramado
Reunión:
Conferencia; THIRD INTERNATIONAL MEETING ON RECENT DEVELOPMENTS IN THE STUDY OF RADIATION EFFECTS IN MATTER.; 2010
Institución organizadora:
Ion Implantation group of the Physics Institute of the Universidade Federal of Rio Grande
Resumen:
We present a theoretical study on
the energy loss of ions
in solids, its mean value or stopping power, the quadratic dispersion
or energy loss straggling. The formalism employed is the shellwise
local plasma approximation (SLPA). This formalism, proposed
originally by Lindhard many years ago, has evolved in the last
years by considering the independent shells of electrons and the
ionization threshold of each shell explicitly.
The SLPA has the advantage of dealing
with very heavy targets, like Au with 79 electrons, with the same
degree of complexity of much simpler ones, like C or Al. On the other
hand, the same formalism is employed to describe bound electrons of
solids or gas targets,
and to calculate different moments of the energy loss. The only
inputs are the density of each shell of electrons and its binding
energies. No parameters are included.
We will review in this talk the SLPA
results and limits for
ions in solids like Al, Zn or Cu, but also very heavy targets
such as Au, Pb, Bi or W, showing the comparison of the
ab-initio
theoretical calculation with the experimental data and the SRIM
results. We will also present in this opportunity theoretical values
for the mean excitation energy and the comparison with Bethe high
energy limit for the stopping power. As the energy loss of ions in
solids is related to the inner-shell ionization, we also compare SLPA
results for inner-shell ionization cross sections of solids with
experimental data.