Quantum Speed Limits for Quantum Information Processing Tasks
  We derive algebraic bounds on achievable rates for quantum state transfer and entanglement generation in general quantum systems. We apply these bounds to graph-based models of local quantum spin systems to obtain speed limits on these tasks. A comparison to numerical optimal control results for spin chains suggests that unexplored regions of the dynamical landscape may support enhanced performance of key quantum information processing tasks. 
Jeffrey M. Epstein, K. Birgitta Whaley
quant-ph