Single-photon entanglement generation by wavefront shaping in a   multiple-scattering medium
  We demonstrate the control of entanglement of a single photon between several spatial modes propagating through a strongly scattering medium. Measurement of the scattering matrix allows the wavefront of the photon to be shaped to compensate the distortions induced by multiple scattering events. The photon can thus be directed coherently to a single or multi-mode output. Using this approach we show how entanglement across different modes can be manipulated despite the enormous wavefront disturbance caused by the scattering medium. 
Hugo Defienne, Marco Barbieri, Benoit Chalopin, Beatrice Chatel, Ian   A. Walmsley, Brian J. Smith and Sylvain Gigan
quant-ph physics.optics