Optomechanical entanglement between a movable mirror and a cavity field
  We show how stationary entanglement between an optical cavity field mode and a macroscopic vibrating mirror can be generated by means of radiation pressure. We also show how the generated optomechanical entanglement can be quantified and we suggest an experimental readout-scheme to fully characterize the entangled state. Surprisingly, such optomechanical entanglement is shown to persist for environment temperatures above 20K using state-of-the-art experimental parameters. 
D. Vitali, S. Gigan, A. Ferreira, H. R. Boehm, P. Tombesi, A.   Guerreiro, V. Vedral, A. Zeilinger, and M. Aspelmeyer