We present different algorithms for mixed-state multicopy entanglement distillation for pairs of qubits. Our algorithms perform significantly better than the best-known algorithms. Better algorithms can be derived that are tuned for specific initial states. These algorithms are based on a characterization of the group of all locally realizable permutations of the $4^n$ possible tensor products of n Bell states.

• Received 29 July 2002

DOI:https://doi.org/10.1103/PhysRevA.67.022310