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Related papers: How to fool the GHZ and W witnesses

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We introduce the challenges of multi-party quantum entanglement and explain a recent success in learning to take its measure. Given the widely accepted reputation of entanglement as a counter-intuitive feature of quantum theory, we first…

Quantum Physics · Physics 2023-11-21 Songbo Xie , J. H. Eberly

Entanglement is a purely quantum mechanical phenomenon and thus it has no classical analog. On the other hand, coherence is a well-known phenomenon in classical optics and in quantum mechanics. Recent research shows that quantum coherence…

Quantum Physics · Physics 2023-02-14 Anu Kumari , Satyabrata Adhikari

We examine the two-party perfect quantum teleportation of an unknown 1-qubit state in the case of sharing various 3-qubit entangled states between a sender and a receiver: GHZ state, W state and W-like state. We give an impossibility proof…

Quantum Physics · Physics 2026-04-03 Sora Kobayashi , Kei-Ichi Kondo

Bipartite maximally entangled states have the property that the largest Schmidt coefficient reaches its lower bound. However, for multipartite states the standard Schmidt decomposition generally does not exist. We use a generalized Schmidt…

Quantum Physics · Physics 2009-11-12 Sayatnova Tamaryan , Tzu-Chieh Wei , DaeKil Park

We present a way of identifying all kinds of entanglement for three-qubit pure states in terms of the expectation values of Pauli operators. The necessary and sufficient conditions to classify the fully separable, biseparable, and genuine…

Quantum Physics · Physics 2015-06-12 Ming-Jing Zhao , Ting-Gui Zhang , Xianqing Li-Jost , Shao-Ming Fei

This paper presents an efficient method for detecting entanglement in high-dimensional two-qudit states by mapping the Hilbert space onto the space of two qubits. This transformation enables the use of well-established two-qubit…

Quantum Physics · Physics 2026-02-25 Josef Kadlec , Artur Barasiński , Karel Lemr

Quantum correlations between identical particles are at the heart of quantum technologies. Several studies with two identical particles have shown that the spatial overlap and indistinguishability between the particles are necessary for…

Quantum Physics · Physics 2022-09-05 Donghwa Lee , Tanumoy Pramanik , Young-Wook Cho , Hyang-Tag Lim , Seungbeom Chin , Yong-Su Kim

We propose the concept of SLOCC-equivalent basis (SEB) in the multiqubit space. In particular, two special SEBs, the GHZ-type and the W-type basis are introduced. They can make up a more general family of multiqubit states, the GHZ-W-type…

Quantum Physics · Physics 2009-11-13 Lin Chen , Yi-Xin Chen

We discuss the canonical form for a pure state of three identical bosons in two modes, and classify its entanglement correlation into two types, the analogous GHZ and the W types as well known in a system of three distinguishable qubits. We…

Quantum Physics · Physics 2009-11-11 B. Zeng , D. L. Zhou , Z. Xu , L. You

The familiar Greenberger-Horne-Zeilinger (GHZ) states can be rewritten by entangling the Bell states for two qubits with a state of the third qubit, which is dubbed entangled entanglement. We show that in this way we obtain all 8…

Quantum Physics · Physics 2015-10-06 Gabriele Uchida , Reinhold A. Bertlmann , Beatrix C. Hiesmayr

The compositional techniques of categorical quantum mechanics are applied to analyse 3-qubit quantum entanglement. In particular the graphical calculus of complementary observables and corresponding phases due to Duncan and one of the…

Logic in Computer Science · Computer Science 2011-03-17 Bob Coecke , Bill Edwards

We prove experimentally the predicted existence of a three-qubit quantum state with genuine multipartite entanglement which can be certified solely from its separable two-qubit reduced density matrices. The qubits are encoded into different…

Quantum Physics · Physics 2020-08-05 Michal Mičuda , Robert Stárek , Jan Provazník , Olga Leskovjanová , Ladislav Mišta,

We present an interesting monogamy equation for $(2 \otimes 2 \otimes n)$-dimensional pure states, by which a quantity is found to characterize the tripartite entanglement with the GHZ type and W typeentanglements as a whole. In particular,…

Quantum Physics · Physics 2009-11-13 Chang-shui Yu , He-shan Song

We present a classification of three-qubit states based in their three-qubit and reduced two-qubit entanglements. For pure states these criteria can be easily implemented, and the different types can be related with sets of equivalence…

Quantum Physics · Physics 2009-11-13 Carlos Sabín , Guillermo García-Alcaine

Lamata et al. use an inductive approach to classify the entangled pure states of four qubits under stochastic local operations and classical communication (SLOCC) [PRA 75(2), 022318 (2007)]. The inductive method yields a priori ten…

Quantum Physics · Physics 2017-03-01 Miriam Backens

The hierarchy of nonlocality and entanglement in multipartite systems is one of the fundamental problems in quantum physics. We study this topic in three-qubit systems considering the entanglement classification of stochastic local…

Quantum Physics · Physics 2022-06-07 Dian Zhu , Gang-Gang He , Fu-Lin Zhang

Based on quantum complementary relations (QCRs) and a purification scenario, we analyze a class of N-qubit mixed states that are entangled but do not have two-, and genuine three-, four-, ..., N-qubit entanglements. It is shown that…

Quantum Physics · Physics 2009-11-13 Yan-Kui Bai , Ming-Yong Ye , Z. D. Wang

We introduce an entanglement criterion to exclude full separability of quantum states. We present numerical evidence that the criterion is necessary and sufficient for the class of GHZ diagonal three-qubit states and estimate the volume of…

Quantum Physics · Physics 2011-01-04 Otfried Gühne

We construct three-qubit entanglement witnesses with the properties that all the partial transposes have the spanning properties. These witnesses determine faces for separable states whose interior lies in the interior of PPT states, and so…

Quantum Physics · Physics 2016-03-22 Seung-Hyeok Kye

We investigate the properties of different levels of entanglement in graph states which correspond to connected graphs. Combining the operational definition of graph states and the postulates of entanglement measures, we prove that in…

Quantum Physics · Physics 2008-07-11 Jian-Ming Cai , Zheng-Wei Zhou , Guang-Can Guo