Single atom photographed for the first time and it is amusing

Something unusual has been just achieved by a curious PhD student at Oxford's Ion Trap Quantum Computing lab. David Nadlinger, on 12 Feb. 2018, has photographed a strontium atom suspended in air by electric fields, to win 2018 Engineering and Physical Sciences Research Council science photography competition.

The photo “a Single Atom In An Ion Trap”, was taken using ordinary DSLR camera, at Oxford University laboratory.

"The idea of being able to see a single atom with the naked eye had struck me as a wonderfully direct and visceral bridge between the minuscule quantum world and our macroscopic reality. When I set off to the lab with a camera and tripods one quiet Sunday afternoon, I was rewarded with the particular picture of a small, pale blue dot," said Nadlinger.

Strontium atom trapped between electrodes. Image Credit: David Nadlinger/University of Oxford

If you look closely, you will find a pale dot suspended between two electrodes. This small dot is actually a single atom of strontium. Atoms are so small that, a single grain of sand would consist of approximately 5x10¹⁹ atoms. So how is it possible to capture an image of such minuscule thing using an ordinary camera? Actually, the pale dot at the centre is not the actual size of an atom.

To visualize strontium atom powerful lasers were used, which made the atom to glow and apparently look bigger than its size. Although to naked eyes the atom would be still invisible, a little trick of the camera made it easy to capture it.

Zoomed image

"The apparent size you see in the picture is what we'd call optic elaboration," Nadlinger said. "The lens we're seeing it through is not perfect, it's slightly out of focus and slightly overexposed. You could compare it to looking at the stars in the night sky, which appear bright but are actually much, much smaller than the size they seem to be, just because our eyes (or the camera) don't have enough resolution to process them."

To Nadlinger, it was a moment of astonishment, as he did not know that this kind of picture was never taken before. A pioneer in Ion Trap systems and a Noble laureate, Hans Dehmelt once took a picture of barium atom, but it was rejected when the editor thought of it a speck of dust.