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Related papers: Entanglement witnesses with local partial ordering

200 papers

Having common reference frames or aligned coordinate systems, is one of the presumptions in witnessing entanglement in a two-party state possessed by two remote parties. This assumption may fail for many reasons. With an unlimited supply of…

Quantum Physics · Physics 2024-05-31 Vahid Jannessary , Fatemeh Rezazadeh , Sadegh Raeisi , Vahid Karimipour

We demonstrate that non-linear entanglement witnesses can be made particularly useful for entanglement detection in hyper-entangled or multilevel states. We test this idea experimentally on the platform of linear optics using a…

Quantum Physics · Physics 2018-09-12 Vojtěch Trávníček , Karol Bartkiewicz , Antonín Černoch , Karel Lemr

We introduce a general method for the experimental detection of entanglement by performing only few local measurements, assuming some prior knowledge of the density matrix. The idea is based on the minimal decomposition of witness operators…

Quantum Physics · Physics 2009-11-07 O. Guehne , P. Hyllus , D. Bruss , A. Ekert , M. Lewenstein , C. Macchiavello , A. Sanpera

Multipartite entanglement is the key resource allowing quantum devices to outperform their classical counterparts, and entanglement certification is fundamental to assess any quantum advantage. The only scalable certification scheme relies…

Quantum Physics · Physics 2021-07-28 Irénée Frérot , Tommaso Roscilde

Entanglement is solely a quantum property and it can be extremely helpful to test the physics beyond the Standard Model in tabletop experiments with the advent of future quantum technologies. In this work, we provide an entanglement-based…

Quantum Physics · Physics 2025-11-20 Pablo Guillermo Carmona Rufo , Ayush Kumar , Carlos Sabín , Anupam Mazumdar

The problem of entanglement detection for arbitrary spin systems is analyzed. We demonstrate how a single measurement of the squared total spin can probabilistically discern separable from entangled many-particle states. For achieving this…

Quantum Physics · Physics 2016-07-29 Eliahu Cohen , Tobias Hansen , Nissan Itzhaki

We present a nonlinear entanglement detection strategy which detects entanglement that the linear detection strategy fails. We show that when the nonlinear entanglement detection strategy fails to detect the entanglement of an entangled…

Quantum Physics · Physics 2025-03-31 Yiding Wang , Tinggui Zhang , Xiaofen Huang , Shao-Ming Fei

We report an experiment in which one determines, with least tomographic effort, whether an unknown two-photon polarization state is entangled or separable. The method measures whole families of optimal entanglement witnesses. We introduce…

Quantum Physics · Physics 2014-10-29 Jibo Dai , Yink Loong Len , Yong Siah Teo , Berthold-Georg Englert , Leonid A. Krivitsky

In this paper based on the notion of entanglement witness, a new measure of entanglement called floating entanglement witness measure is introduced which satisfies some of the usual properties of a good entanglement measure. By exploiting…

Quantum Physics · Physics 2007-08-28 A. Baghbanpourasl , G. Najarbashi , M. Seyedkazemi

To quantify the entanglement of bipartite systems in terms of some entanglement measure is a challenging problem in general, and it is much worse when the information about the system is less. In this manuscript, based on two classes of…

Quantum Physics · Physics 2024-01-01 Xian Shi

We explore the possibility of entanglement detection in continuous variable systems by entanglement witnesses based on covariance matrices, constructible from random homodyne measurements. We propose new linear constraints characterizing…

Quantum Physics · Physics 2021-01-20 Tatiana Mihaescu , Hermann Kampermann , Giulio Gianfelici , Aurelian Isar , Dagmar Bruss

We show that magnetic susceptibility can reveal spin entanglement between individual constituents of a solid, while magnetisation describes their local properties. We then show that these two thermodynamical quantities satisfy complementary…

Quantum Physics · Physics 2009-11-11 M. Wiesniak , V. Vedral , C. Brukner

Entanglement is a key resource to demonstrate quantum advantage over classical strategies. Entanglement in quantum states is one of the most well-explored areas in quantum physics. However, a rigorous approach to understanding and detecting…

Quantum Physics · Physics 2025-02-12 Shubhayan Sarkar

We present several criteria for genuine multipartite entanglement from universal uncertainty relations based on majorization theory. Under non-negative Schur-concave functions, the vector-type uncertainty relation generates a family of…

Quantum Physics · Physics 2016-07-07 Yunlong Xiao , Naihuan Jing , Xianqing Li-Jost , Shao-Ming Fei

Recent progress in theories of quantum information has determined nonclassical correlation defined differently from widely-used entanglement as an important property to evaluate computation and communication with mixed quantum states. We…

Quantum Physics · Physics 2010-08-13 Robabeh Rahimi , Akira SaiToh

In this work, we present a practical and efficient framework for verifying entangled states when only a tomographically incomplete measurement setting is available-specifically, when access to observables is severely limited. We show how…

While it is usually known that the mean value of a single observable is enough to detect entanglement or its distillability, the counterpart of such an approach in the case of quatum privacy has been missing. Here we develop the concept of…

Quantum Physics · Physics 2013-05-30 Konrad Banaszek , Karol Horodecki , Paweł Horodecki

We transform the way of finding entanglement criterion into two steps: to obtain necessary criterion of separability by maximizing an algebra function for a set of characteristic variables of the witness operator and the given number of…

Quantum Physics · Physics 2016-05-30 Xiao-yu Chen , Zhu-an Xu

Based on the general form of entanglement witnesses constructed from separable states, we first show a sufficient condition of violating the structural physical approximation (SPA) conjecture [Phys. Rev. A 78, 062105 (2008)]. Then we…

Quantum Physics · Physics 2012-10-15 Bang-Hai Wang , Dong-Yang Long

Quantum nonlocality is often judged by violations of Bell-type inequalities for a given state. The computation of such violations is a global task, requiring evaluation of global correlations and subsequent testing against a Bell…

Quantum Physics · Physics 2025-11-04 Rohit Kishan Ray