title: Witnessing genuine multipartite entanglement with positive maps.
abstract: We derive a general framework that lifts any set of bipartite to multipartite entanglement witnesses and we show how positive maps can naturally be incorporated into this framework. We show that some previous approaches for multipartite entanglement detection are intimately connected to the witnesses derived from partial transposition and that such criteria can easily be outperformed in higher dimensions by nondecomposable maps. As an exemplary case we present a witness that is capable of detecting genuine multipartite entanglement in bound entangled states.
authors.affiliation: ICFO-Institut de Ciencies Fotoniques, 08860 Castelldefels, Barcelona, Spain and Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Marcus
authors.initials: M
authors.lastname: Huber
authors.affiliation: Department of Mathematical Sciences, Indian Institute of Science Education and Research Mohali, Mohali 140306, India and Theoretical Statistics and Mathematics Unit, Indian Statistical Institute, 7 S.J.S. Sansanwal Marg, New Delhi 110 016, India.
authors.forename: Ritabrata
authors.initials: R
authors.lastname: Sengupta