The "miracle material" graphene - a two-dimensional honeycomb structure made of carbon atoms with a thickness of only one atom - has numerous outstanding properties. These include enormous mechanical resistance and extraordinary electronic and optical properties. Last year a team led by the Empa researcher Roman Fasel was able to show that it can even be magnetic: they succeeded in synthesizing a molecule in the shape of a bowtie, which has special magnetic properties.
Now another breakthrough has been made in this direction. Theoretical work from 2007 predicted that graphene could exhibit magnetic behaviour if it were cut into tiny triangles. Over the last three years, several teams, including the Empa team, have succeeded in producing the so-called triangulenes, consisting of only a few dozen carbon atoms, by chemical synthesis under ultra-high vacuum.
On the track of magnetism with the scanning tunneling microscope
However, their magnetism had remained undiscovered until now. First, the presence of unpaired spins, which make triangulenes magnetic in the first place, also make them extremely reactive. Secondly, even with stable molecules, it is extremely difficult to prove the magnetism of such a tiny piece of matter. But now an international group of scientists from Empa, the Technical University of Dresden, the University of Alicante and the International Iberian Nanotechnology Laboratory in Portugal has succeeded in doing just that.To read more, click here.