Australian researchers capture image of atom
06 July 2012
In a unique achievement, researchers at Griffith University in Brisbane, Australia, have recorded for the first time the image of an atom's shadow.
The researchers used a custom-made ion trap, capable of holding a single atom at a time. Once that was done, they focused light of the correct wavelength past the atom to cause a shadow, a very, very small shadow at that.
To make the exercise easier, they started with a big atom - Ytterbium , with an atomic mass of 174 - and cooled it right down to -273°C to stabilise it. They then trained a beam on light on it and captured the resulting shadow using a Fresnel lens.
The amazing achievement, might help serve a useful purpose too. According to the researchers, the techniques could be used for the creation of extremely high-res biological imaging systems, that could monitor samples like DNA without damaging them.
Professor Dave Kielpinski of Griffith University's Centre for Quantum Dynamics said, with the experiment the researchers had reached the extreme limit of microscopy; and it was not possible to see anything smaller than an atom using visible light.
He added, they wanted to investigate, how few atoms were required to cast a shadow and proved it took just one.