144 citations · 177 across the 3 of their papers we have counts for
4 papers · 1 filter
Generalized Ardehali-Bell inequalities for graph states
Otfried Gühne, Adan Cabello
We derive Bell inequalities for graph states by generalizing the approach proposed by Ardehali [Phys. Rev. A 46, 5375 (1992)] for Greenberger-Horne-Zeilinger (GHZ) states. Using th…
Toolbox for entanglement detection and fidelity estimation
Otfried Gühne, Chao-Yang Lu, Wei-Bo Gao +1
The determination of the state fidelity and the detection of entanglement are fundamental problems in quantum information experiments. We investigate how these goals can be achieve…
Parameter estimation for mixed states from a single copy
Thomas Konrad, Otfried Gühne, Jürgen Audretsch +1
Given a single copy of a mixed state of the form ρ=λρ_1+(1-λ)ρ_2, what is the optimal measurement to estimate the parameter λ, if ρ_1 and ρ_2 are known? We present a general strate…
Nonlinear entanglement witnesses, covariance matrices and the geometry of separable states
Otfried Gühne, Norbert Lütkenhaus
Entanglement witnesses provide a standard tool for the analysis of entanglement in experiments. We investigate possible nonlinear entanglement witnesses from several perspectives.…