Intrinsic decoherence and classical-quantum correspondence in two   coupled delta-kicked rotors
  We show that classical-quantum correspondence of center of mass motion in two coupled delta-kicked rotors can be obtained from intrinsic decoherence of the system itself which occurs due to the entanglement of the center of mass motion to the internal degree of freedom without coupling to external environment. 
Hwa-Kyun Park, Sang Wook Kim