For decades, physicists have mused over the theoretical properties of Luttinger liquids, strange one-dimensional quantum states in which charge and magnetic spin of particles are predicted to decouple and move at different speeds.

Dimitris Angelakis at the Technical University of Crete, Greece, and his colleagues have taken a step towards creating a Luttinger liquid in the lab. They propose a practical scheme whereby two different types of atom would be trapped in a hollow, one-dimensional optic fibre and tuned with two sets of opposing laser beams. When one pair of beams is switched off, the authors show, a photon pulse in which charge and spin are decoupled will move along the fibre.

Phys. Rev. Lett. 106, 153601 (2011)