Download Prof. Dr. W. Demtröder

EINLADUNG ZUM SONDERSEMINAR
im Rahmen des Seminars über ultraschnelle Phänomene und SFB/TRR 88 3MET
Mittwoch, 09.07.2014, 17:00 Uhr, Raum 52-206
Es spricht:
Dr. Andrea Droghetti
School of Physics, CRANN and AMBER centers, Trinity College Dublin
Thema:
From organic to single-molecule spintronics:
a theoretical prospective on some open issues
In the recent years, a large effort has been devoted to investigate the characteristic behavior
of spintronic devices incorporating organic molecules. On the one hand, hybrid spin-valves,
in which the non-magnetic spacer is composed by an organic semiconductor thick film, have
been first considered. On the other hand, the ultimate challenge of understanding spintransport through single molecules has also been undertaken. Both these research lines has
now grown into mature research fields called respectively organic and molecular spintronics.
In this context, we here discuss some important issues, which we have addressed in the
recent years and we provide a personal point of view for future developments of these fields.
In the case of organic spintronics, we highlight how interface states play a crucial role in
affecting spininjection from a ferromagnetic metal into an organic semiconductor. We further
demonstrate how the hybrid ferromagnet/organic interfaces can be functionalized by
exploiting molecules with a vast range of properties, which go from large electron affinity to
magnetism. Then we suggest how future studies will need to focus on unraveling the spin
dynamics and the spin relaxation mechanisms at these hybrid interfaces. In the case of
molecular spintronics,, we point out how the standard concepts beyond both inorganic and
organic spintronics can not be easily carried over to the single-molecule scale either
because of fundamental or practical limitations. These extends from the experimental
problem of realizing ferromagnetic electrodes to the fundamental fact that the energy of the
magnetic anisotropy and of the exchange coupling in molecules never exceeds few kelvins.
We then illustrate how some developments in the field may come by using molecules, which
can be easily switched between different states, or by employing graphene electrodes. The
research presented has been carried out within the European Union funded project HINTS
and the young explorers FET project ACMOL.
Der Gast wird betreut von Dr. habil. M. Cinchetti
Gäste sind herzlich willkommen!