Speaker
Tatiana Mihaescu
(Department of Theoretical Physics, National Institute of Physics & Nuclear Engineering, RO-077125 Bucharest-Magurele, Romania; Faculty of Physics, University of Bucharest, RO-077125 Bucharest-Magurele, Romania)
Description
We define and fully characterize the witnesses based on second moments detecting steering in Gaussian states by means of Gaussian measurements. All such tests, which arise from linear combination of variances or second moments of canonical operators, are easily implemented in experiments. We propose also a set of linear constraints characterizing steering witnesses. Given an unknown quantum state we implement a semidefinite program providing the optimal steering test with respect to the number of random measurements performed. We study the efficiency of steering detection for squeezed vacuum states and for general unknown covariance matrices. In addition, we discuss the robustness of this method to statistical errors.
Primary authors
Tatiana Mihaescu
(Department of Theoretical Physics, National Institute of Physics & Nuclear Engineering, RO-077125 Bucharest-Magurele, Romania; Faculty of Physics, University of Bucharest, RO-077125 Bucharest-Magurele, Romania)
Hermann Kampermann
(Heinrich-Heine-University Düsseldorf, Institute of Theoretical Physics III, D-40225 Düsseldorf, Germany)
Aurelian Isar
(Department of Theoretical Physics, National Institute of Physics & Nuclear Engineering, RO-077125 Bucharest-Magurele, Romania; Faculty of Physics, University of Bucharest, RO-077125 Bucharest-Magurele, Romania)
Dagmar Bruss
(Heinrich-Heine-University Düsseldorf, Institute of Theoretical Physics III, D-40225 Düsseldorf, Germany)
