Physicist Gopakumar is working with |
Using
individual molecules instead of electronic or magnetic memory cells
would revolutionize data storage technology, as molecular memories could
be thousand-fold smaller. Scientists of Kiel University took a big step
towards developing such molecular data storage. They succeeded in
selectively switching on and off the magnetism of individual molecules,
so-called spin-crossover complexes, by electrons.
The
interdisciplinary study is part of the Collaborative Research Centre
677 “Functions by Switching”, which is funded by the German Research
Foundation (DFG). The results prove that it is technically possible to
store information using molecules. The study will be published on June
25, 2012, in the German science magazine Angewandte Chemie.
“In
principle information may be stored in a single molecule. However,
techniques that would make such an approach feasible are becoming
available just now”, explains project leader Professor Richard Berndt of
the Institute of Experimental and Applied Physics at Kiel University.
Since
the 1980s scientists are able to image individual molecules on surfaces
with scanning tunneling microscopes, he continues. Current research
aims at controlling the characteristics of single molecules in order to
facilitate future technical applications. The Collaborative Research
Centre 677 “Functions by Switching” at Kiel University is a large-scale
project engaged in such investigations, which aim at constructing
molecular machines.
The
current study is focused on the magnetism of molecules. Using a
scanning tunneling microscope Dr. Thiruvancheril Gopakumar, who carried
out the study, was able to switch individual molecules between two
magnetic states. Despite their dense packing in a molecular layer he was
able to target individual molecules for switching.
Computer graphic of the spin-crossover molecule that was used for the experiments on gold surface and the STM images of its different magnetic states |
“Many
research groups are striving to control the magnetic characteristics of
molecules. Gopakumar’s studies have taken us one step ahead,” says
Berndt.
The molecules (spin-crossover complexes) were synthesized at the Institute of Inorganic Chemistry at Kiel University.
“Even
though it took us a long time to find adequate molecules, we are very
pleased with the outcome”, states Professor Felix Tuczek, head of the
research group “Inorganic Molecular Chemistry”. The next step will be to
adapt the molecules in a way that would allow scientists to switch them
with light instead of electrons and at higher temperatures.
Electron-induced spin crossover of single molecules in a bilayer on gold
Source: University of Kiel
