Atoms and light form cool, complex patterns

The physics behind some of nature’s spectacular sights have been observed at very low temperatures - less than a thousandth of a degree away from absolute zero - by researchers from the University of Strathclyde in Glasgow, UK, and the Institut Non Linéaire de Nice in Sophia-Antipolis, France.

They're investigating complex structures and patterns which can emerge from the way natural systems organise themselves. Examples include cellular patterns formed by heated oil in frying pans and hexagonal patterns on a giraffe's skin, as well as the highly-sophisticated, laser-driven atomic samples being investigated in the Strathclyde and Nice laboratories.

The researchers want to understand the way these structures arrange themselves spontaneously, by studying ultra-cold atomic vapours. They previously developed a theory predicting the conditions under which patterns should emerge.

Now they've carried out further experiments which have shown that, under these conditions, the light and atoms arrange themselves to form striking hexagon and honeycomb patterns.

These self-organised structures of ultra-cold atoms and light may open up new possibilities for manipulating and structuring matter. They could have an impact in various branches of physics, including quantum, nonlinear and condensed-matter physics.

The results have been published in the journal Nature Photonics.

Professor Thorsten Ackemann, of Strathclyde's Department of Physics and co-leader of the research, said:

The experimental results demonstrate this novel type of cooperation between matter and light. They enable the self-organised manipulation of the density of matter itself, which is an intriguing and unusual feature.