title: Entangled Pure State Transformations via Local Operations Assisted by Finitely Many Rounds of Classical Communication.
abstract: We consider generic pure n-qubit states and a general class of pure states of arbitrary dimensions and arbitrarily many subsystems. We characterize those states which can be reached from some other state via local operations assisted by finitely many rounds of classical communication (LOCC_{N}). For n qubits with n>3, we show that this set of states is of measure zero, which implies that the maximally entangled set is generically of full measure if restricted to the practical scenario of LOCC_{N}. Moreover, we identify a class of states for which any LOCC_{N} protocol can be realized via a concatenation of deterministic steps. We show, however, that in general there exist state transformations which require a probabilistic step within the protocol, which highlights the difference between bipartite and multipartite LOCC.
authors.affiliation: Institute for Theoretical Physics, University of Innsbruck, Technikerstraße 21a, A-6020 Innsbruck, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Spee
authors.affiliation: Departamento de Matemáticas, Universidad Carlos III de Madrid, Avenida de la Universidad 30, E-28911 Leganés, Madrid, Spain.
authors.forename: J I
authors.initials: JI
authors.lastname: de Vicente
authors.affiliation: Institute for Theoretical Physics, University of Innsbruck, Technikerstraße 21a, A-6020 Innsbruck, Austria.
authors.forename: D
authors.initials: D
authors.lastname: Sauerwein
authors.affiliation: Institute for Theoretical Physics, University of Innsbruck, Technikerstraße 21a, A-6020 Innsbruck, Austria.
authors.forename: B
authors.initials: B
authors.lastname: Kraus