Light relief

On reflection, it is possible to hold a single light-emitting molecule in a tiny cavity and have the photon it emits bounce back and so co-exist with the molecule in a light-molecule mixture. Such a state of affairs might be exploited in quantum devices of the future, according to work by researchers at the University of Cambridge, King’s College and Imperial College London. "It's like a hall of mirrors for a molecule, only spaced a hundred thousand times thinner than a human hair," explains Cambridge's Jeremy Baumberg. Many months of spectroscopy, data collection and statistical analysis revealed the first evidence of single-molecule strong coupling, on which the team reports in the journal Nature.