Posted: June 17, 2009

Photons know what other photons do

(Nanowerk News) When light propagates through multiple scattering media such as clouds, white paint, or nano-photonic devices, classical information for example the direction of propagation tends to be lost. Surprisingly this turns out to be different for quantum light.
light propagating through multiple scattering media
Now, Stephan Smolka and co-workers published in Physical Review Letters 102, 193901 (May 2009) the experimantal demonstration that spatial quantum correlations are induced when quantum correlated light is sent through a multiple scattering medium.
As a consequence, the number of photons scattered into one direction can be predicted from the number of photons detected in a different direction. The magnitude of the spatial quantum correlations could be controlled by changing the quantum state of light incident on the medium.
Source: Technical University of Denmark