Universal Dynamical Control of Local Decoherence for Multipartite and   Multilevel Systems
  A unified theory is given of dynamically modified decay and decoherence of field-driven multilevel multipartite entangled states that are weakly coupled to zero-temperature baths or undergo random phase fluctuations. The theory allows for arbitrary local differences in their coupling to the environment. Due to such differences, the optimal driving-field modulation to ensure maximal fidelity is found to substantially differ from conventional ``Bang-Bang'' or $\pi$-phase flips of the single-qubit evolution. 
Goren Gordon, Gershon Kurizki and Abraham G. Kofman