| Jul 03, 2012 |
First photo of atom's shadow |
| (Nanowerk News) A pixelated image of a black spot on an orange background isn't likely to win any photographic competitions. |
| But the seemingly bland image, taken by scientists at Queensland's Griffith University, could potentially revolutionise mankind's understanding of physics and how the world works. |
| A research team at the university's centre for quantum dynamics in Brisbane has been able to photograph the shadow of a single atom for the first time (see paper in Nature Communications: "Absorption imaging of a single atom"). |
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| Artist's illustration of a single atom shadow. (Image: Kielpinski group, Griffith University) |
| Professor Dave Kielpinski says the image is at the extreme limit of microscopy. |
| "You cannot see anything smaller than an atom using visible light," Prof Kielpinski said in a statement. |
| "We wanted to investigate how few atoms are required to cast a shadow, and we proved it takes just one." |
| The scientists used a super high-resolution microscope not available anywhere else in the world. |
| A single atom of the element ytterbium was held by electrical forces and exposed to a specific frequency of light, which caused it to cast a shadow that could be photographed. |
| Research team member Erik Streed said the photo had myriad implications, including revolutionising quantum computing and biomicroscopy. |
| "Because we are able to predict how dark a single atom should be, as in how much light it should absorb in forming a shadow, we can measure if the microscope is achieving the maximum contrast allowed by physics," Dr Streed said. |
| "This is important if you want to look at very small and fragile biological samples such as DNA strands where exposure to too much UV light or x-rays will harm the material." |
| Source: Griffith University |
