Researchers have mixed molecules with light at room temperature. It's the first time such a feat has been accomplished.

Scientists did so by trapping a colored dye molecule in a gap between a gold nanoparticle and a mirror. The gap measured just one nanometer across.

Normally, when a molecule emits light, the photon escapes never to return. In this case, the light particle is prevented from fully escaping by the mirror -- its energy oscillating between light and molecule. The two entities become one.

"It's like a hall of mirrors for a molecule, only spaced a hundred thousand times thinner than a human hair," lead researcher Jeremy Baumberg, a scientist with the NanoPhotonics Centre at Cambridge's Cavendish Laboratory, explained in a news release.

Researchers described their novel feat in a new paper, published this week in the journal Nature.

The nanoscale hall of mirrors would have been a waste if scientists hadn't also figured out how to properly position their dye molecule.

"Our molecules like to lie down flat on the gold, and it was really hard to persuade them to stand up straight," said lead study author Rohit Chikkaraddy.

A hollow barrel-like molecular cage known as a cucurbiturils did the trick, keeping the molecule in an upright position.

The split of the molecule's emissions spectrum into two quantum states served as proof of mixing between the light and molecule.

Proving that light and molecule mixing was possible was difficult, but now scientists are developing ways to use the phenomenon to manipulate the physical and chemical properties of matter. Researchers think the technology could also be used to process quantum information.