Generation of two-mode entanglement via atomic coherence created by   non-resonant dressed-state transitions
  Two-mode squeezing and entanglement is obtained in a atom-cavity system cosisting a three-level atom and a two-mode cavity with driving laser fields. Here non-resonatn dressed-state transitions between the cavity modes and atom are used to get the effective Hamiltonian. 
Jinhua Zou, Dahai Xu and Huafeng Zhang
quant-ph physics.optics