This remarkable photo shows a single atom trapped by electric fields.
The image was shot by David Nadlinger, at the University of Oxford. The photograph was taken through a window of the ultra-high vacuum chamber that houses an ion trap.
In the centre of the picture, a small bright dot is visible – a single positively-charged strontium atom. It is held nearly motionless by electric fields emanating from the metal electrodes surrounding it. (The distance between the small needle tips is about two millimetres.) When illuminated by a laser of the right blue-violet colour, the atom absorbs and re-emits light particles sufficiently quickly for an ordinary camera to capture it in a long exposure photograph. This picture was taken through a window of the ultra-high vacuum chamber that houses the trap. Laser-cooled atomic ions provide a pristine platform for exploring and harnessing the unique properties of quantum physics. They are used to construct extremely accurate clocks or, as in this research, as building blocks for future quantum computers, which could tackle problems that stymie even today’s largest supercomputers. [Taken on Aug 7, 02:36 in Clarendon Laboratory -172; Canon 5D Mk II, EF 50mm f/1.8 with extension tubes, two flash units with colour gels.] Image Caption
The photo shows an atom as a speck of light between two metal electrodes placed about 2mm (0.078in) apart. The photograph is only possible because the atom is receiving energy from a laser which causes it to emit light. To the naked eye, it would look far dimmer – the photograph itself uses a long exposure shot to make it visible.
The photo itself was captured last August using a Canon 5D Mark II DSLR, a Canon EF 50mm f/1.8 lens on an extension tube. Two flash units with color gels lit the room.
The image scooped the prestigious national science photography competition award from the Engineering and Physical Sciences Research Council (EPSRC). The competition received over 100 entries which were drawn from researchers in receipt of EPSRC funding.
Find out more about the image, and see the runners up in competition at epsrc.ac.uk