Photonic Maxwell’s demon

By analogy with Maxwell’s original thought experiment, the setup uses energy extracted from a thermal system.

Physical Review Letters 116, 50401 (2016)

M. Vidrighin, O. Dahlsten, M. Barbieri, M. Kim, V. Vedral, I. Walmsley

By analogy with Maxwell’s original thought experiment, the setup uses energy extracted from a thermal system.

We report an experimental realization of Maxwell’s demon in a photonic setup. We show that a measurement at the few-photons level followed by a feed-forward operation allows the extraction of work from intense thermal light into an electric circuit. The interpretation of the experiment stimulates the derivation of an equality relating work extraction to information acquired by measurement. We derive a bound using this relation and show that it is in agreement with the experimental results. Our work puts forward photonic systems as a platform for experiments related to information in thermodynamics.