Detecting multipartite entanglement structure with minimal resources

Detecting multipartite entanglement

Andrew C. Doherty, Pablo A. Parrilo, and Federico M. Spedalieri School of Physical Sciences, University of Queensland, St Lucia, Queensland 4072, Australia Institute for Quantum Information, California Institute of Technology, Pasadena, California 91125, USA Institut für Automatik, ETH Zentrum, CH-8092 Zürich, Switzerland Quantum Computing Technologies Group, Jet Propulsion Laboratory, Pasadena...

Witnessing Multipartite Entanglement by Detecting Asymmetry

The characterization of quantum coherence in the context of quantum information theory and its interplay with quantum correlations is currently subject of intense study. Coherence in a Hamiltonian eigenbasis yields asymmetry, the ability of a quantum system to break a dynamical symmetry generated by the Hamiltonian. We here propose an experimental strategy to witness multipartite entanglement i...

Detecting genuine multipartite entanglement with two local measurements.

We present entanglement witness operators for detecting genuine multipartite entanglement. These witnesses are robust against noise and require only two local measurement settings when used in an experiment, independent of the number of qubits. This allows detection of entanglement for an increasing number of parties without a corresponding increase in effort. The witnesses presented detect sta...

Detecting genuine multipartite entanglement of pure states with bipartite correlations

The Compositional Structure of Multipartite Quantum Entanglement

While multipartite quantum states constitute a (if not the) key resource for quantum computations and protocols, obtaining a high-level, structural understanding of entanglement involving arbitrarily many qubits is a longstanding open problem in quantum computer science. In this paper we expose the algebraic and graphical structure of the GHZ-state and the W-state, as well as a purely graphical...