Photon phonon entanglement in coupled optomechanical arrays
  We consider an array of three optomechanical cavities coupled either reversibly or irreversibly to each other and calculate the amount of entanglement between the different optical and mechanical modes. We show the composite system exhibits intercavity photon-phonon entanglement. 
Uzma Akram, William Munro, Kae Nemoto and G. J. Milburn
quant-ph cond-mat.mes-hall