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Related papers: Multiqubit entanglement witness

200 papers

We have studied the generation of multipartite entangled states for the superconducting phase qubits. The experiments performed in this direction have the capacity to generate several specific multipartite entangled states for three and…

Quantum Physics · Physics 2014-10-21 Mazhar Ali

Entanglement witnesses (EWs) are a fundamental tool for the detection of entanglement. We investigate the inertias of bipartite EWs constructed by the partial transpose of NPT states. Furthermore, we find out most of the inertias of the…

Quantum Physics · Physics 2022-04-21 Changchun Feng , Lin Chen , Chang Xu , Yi Shen

Entanglement is one of the most studied properties of quantum mechanics for its application in quantum information protocols. Nevertheless, detecting the presence of entanglement in large multipartite sates continues to be a great challenge…

Quantum Physics · Physics 2017-06-21 Flavio Baccari , Daniel Cavalcanti , Peter Wittek , Antonio Acín

We develop a novel necessary condition of quantum correlation. It is utilized to construct $d$-level bipartite Bell-type inequality which is strongly resistant to noise and requires only analyses of $O(d)$ measurement outcomes compared to…

Quantum Physics · Physics 2007-09-14 Che-Ming Li , Li-Yi Hsu , Yueh-Nan Chen , Der-San Chuu , Tobias Brandes

Entanglement is a central concept in quantum information and a key resource for many quantum protocols. In this work we propose and analyze a class of entanglement witnesses that detect the presence of entanglement in subsystems of…

Quantum Physics · Physics 2020-01-22 David Amaro , Markus Müller

We introduce an experimental procedure for the detection of quantum entanglement of an unknown quantum state with as few measurements as possible. The method requires neither a priori knowledge of the state nor a shared reference frame…

Entanglement witnesses are nonpositive Hermitian operators which can detect the presence of entanglement. In this paper, we provide a general parametrization for orthonormal basis of ${\mathbb C}^n$ and use it to construct projector-based…

Quantum Physics · Physics 2010-03-16 S. J. Akhtarshenas , A. Kheirollahi

The experimental verification of multipartite entangled states is essential for advancing quantum information processing. Entanglement witnesses (EWs) provide a widely used and experimentally accessible approach for detecting genuinely…

Quantum Physics · Physics 2025-09-03 Tomis Prajapati , Harsh Mehta , Shreya Banerjee , Prasanta K. Panigrahi , V. Narayanan

We consider a scenario where spatially separated observers share a genuinely multiparty entangled quantum state with each local observer possessing a single qubit. A particular qubit is acted upon by sequential and independent observers. We…

Quantum Physics · Physics 2025-09-19 Chirag Srivastava , Mahasweta Pandit , Ujjwal Sen

A typical concept in quantum state analysis is based on the idea that states in the vicinity of some pure entangled state share the same properties; implying that states with a high fidelity must be entangled. States whose entanglement can…

Quantum Physics · Physics 2021-04-12 Otfried Gühne , Yuanyuan Mao , Xiao-Dong Yu

We propose a family of positive maps constructed from a recently introduced class of symmetric measurements. These maps are used to define entanglement witnesses, which include other popular approaches with mutually unbiased bases and…

Quantum Physics · Physics 2022-02-09 Katarzyna Siudzińska

We study entanglement witness and present a construction of entanglement witnesses in terms of the mutually unbiased measurements (MUMs). These witnesses include the entanglement witnesses constructed from mutually unbiased bases (MUBs) as…

Quantum Physics · Physics 2019-12-05 Tao Li , Le-Min Lai , Shao-Ming Fei , Zhi-Xi Wang

Quantum entanglement detection and characterization are crucial for various quantum information processes. Most existing methods for entanglement detection rely heavily on a complete description of the quantum state, which requires numerous…

Quantum Physics · Physics 2025-04-21 Rui Li , Shikun Zhang , Zheng Qin , Chunxiao Du , Yang Zhou , Zhisong Xiao

We present a class of entanglement identifiers which has the following experimentally friendly feature: once the expectation value of the identifier exceeds some definite limit, we can conclude the state is entangled, even if not all…

Quantum Physics · Physics 2013-08-22 Wieslaw Laskowski , Marcin Markiewicz , Tomasz Paterek , Ryszard Weinar

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

The purpose of an entanglement witness experiment is to certify the creation of an entangled state from a finite number of trials. The statistical confidence of such an experiment is typically expressed as the number of observed standard…

Quantum Physics · Physics 2020-04-29 Bas Dirkse , Matteo Pompili , Ronald Hanson , Michael Walter , Stephanie Wehner

We discuss several aspects of multiparticle mixed state entanglement and its experimental detection. First we consider entanglement between two particles which is robust against disposals of other particles. To completely detect these kinds…

Quantum Physics · Physics 2009-11-06 W. Dür , J. I. Cirac

Monogamy of bipartite correlations leads, for arbitrary pure multi-qubit states, to simple conditions able to indicate various types of multipartite entanglement by being capable to exclude the possibility of k-separability.

Quantum Physics · Physics 2013-04-09 Marcin Markiewicz , Wieslaw Laskowski , Tomasz Paterek , Marek Zukowski

Entanglement witnesses are one of the most effective methods to detect entanglement. It is known that nonlinear entanglement witnesses provide better entanglement detection than their linear counterparts, in that the former detect a…

Quantum Physics · Physics 2025-12-25 Kornikar Sen , Chirag Srivastava , Ujjwal Sen

We show how to quantify tri-partite entanglement using entropies derived from experimental correlations. We use a multi-partite generalization of the entanglement of formation that is greater than zero if and only if the state is genuinely…

Quantum Physics · Physics 2020-11-04 James Schneeloch , Christopher C. Tison , Michael L. Fanto , Shannon Ray , Paul M. Alsing