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Related papers: Entanglement in eight-qubit graph states

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We propose a technique to investigate multipartite entanglement in the symmetric subspace. Our approach is to map an $N$-qubit symmetric state onto a bipartite symmetric state of higher local dimension. We show that this mapping preserves…

Quantum Physics · Physics 2025-10-07 Carlo Marconi , Satoya Imai

We introduce a class of multiqubit quantum states which generalizes graph states. These states correspond to an underlying mathematical hypergraph, i.e. a graph where edges connecting more than two vertices are considered. We derive a…

Quantum Physics · Physics 2013-11-13 M. Rossi , M. Huber , D. Bruß , C. Macchiavello

We classify the local unitary equivalence classes of absolutely maximally entangled (AME) states of five qubits. We show that every 5-qubit AME state is equivalent to a state within the unique ((5,2,3)) quantum error-correcting code…

Quantum Physics · Physics 2026-05-20 Ian Tan

A classification of multipartite entanglement in qubit systems is introduced for pure and mixed states. The classification is based on the robustness of the said entanglement against partial trace operation. Then we use current machine…

Quantum Physics · Physics 2022-10-17 F. El Ayachi , M. El Baz

Graph states are a powerful class of entangled states with numerous applications in quantum communication and quantum computation. Local Clifford (LC) operations that map one graph state to another can alter the structure of the…

Quantum Physics · Physics 2026-02-11 Hemant Sharma , Kenneth Goodenough , Johannes Borregaard , Filip Rozpędek , Jonas Helsen

A quantum state's entanglement across a bipartite cut can be quantified with entanglement entropy or, more generally, Schmidt norms. Using only Schmidt decompositions, we present a simple iterative algorithm to maximize Schmidt norms.…

Quantum Physics · Physics 2018-06-14 Robin Reuvers

Graph states play an important role in quantum information theory through their connection to measurement-based computing and error correction. Prior work has revealed elegant connections between the graph structure of these states and…

Quantum Physics · Physics 2025-04-15 Louis Schatzki , Linjian Ma , Edgar Solomonik , Eric Chitambar

The class of entangled $N$-qubit states known as graph states, and the corresponding stabilizer groups of $N$-qubit Pauli observables, have found a wide range of applications in quantum information processing and the foundations of quantum…

Quantum Physics · Physics 2014-09-26 Mordecai Waegell

The Schmidt measure was introduced by Eisert and Briegel for quantifying the degree of entanglement of multipartite quantum systems [Phys. Rev. A 64, 022306 (2001)]. Although generally intractable, it turns out that there is a bound on the…

Quantum Physics · Physics 2007-05-23 Simone Severini

We investigate bipartite entanglement in qubit hypergraph states across an arbitrary fixed bipartition. Using the real equally weighted (REW) representation, the Schmidt rank across the cut can be computed as the real rank of a…

Quantum Physics · Physics 2026-02-25 C. Fajardo , M. Paraschiv

Classifying states as entangled or separable is a highly challenging task, while it is also one of the foundations of quantum information processing theory. This task is higly nontrivial even for relatively simple cases, such as two-qutrit…

Quantum Physics · Physics 2022-11-08 Marcin Wieśniak

We propose a scalable and deterministic protocol for growing large multi-qubit states starting from two-qubit non-maximally entangled pure states, where the bipartite entanglement in the resultant state is higher than the maximum of the…

Quantum Physics · Physics 2026-04-28 Harikrishnan K J , Amit Kumar Pal

We investigate a family of quantum states defined by directed graphs, where the oriented edges represent interactions between ordered qubits. As a measure of entanglement, we adopt the Entanglement Distance - a quantity derived from the…

Quantum Physics · Physics 2025-05-19 Lucio De Simone , Roberto Franzosi

Stabilizer states are a prime resource for a number of applications in quantum information science, such as secret-sharing and measurement-based quantum computation. This motivates us to study the entanglement of noisy stabilizer states…

Quantum Physics · Physics 2024-11-01 Kenneth Goodenough , Aqil Sajjad , Eneet Kaur , Saikat Guha , Don Towsley

Bipartite correlations in multi-qubit systems cannot be shared freely. The presence of entanglement or classical correlation on certain pairs of qubits may imply correlations on other pairs. We present a method of characterization of…

Quantum Physics · Physics 2009-11-10 Martin Plesch , Vladimir Buzek

In this paper we consider the separability problem for bipartite quantum states arising from graphs. Earlier it was proved that the degree criterion is the graph-theoretic counterpart of the familiar positive partial transpose criterion for…

Quantum Physics · Physics 2016-07-29 Supriyo Dutta , Bibhas Adhikari , Subhashish Banerjee , R. Srikanth

We introduce a protocol to classify three-qubit pure states into different entanglement classes and implement it on an NMR quantum processor. The protocol is designed in such a way that the experiments performed to classify the states can…

Quantum Physics · Physics 2024-11-07 Vaishali Gulati , Arvind , Kavita Dorai

Systems of four nonbinary particles, each having three or more internal states, exhibit maximally entangled states that are inaccessible to four qubits. This breaks the pattern of two- and three-particle systems, in which the existing graph…

Quantum Physics · Physics 2015-06-23 Mario Gaeta , Andrei Klimov , Jay Lawrence

In this paper we give a method to associate a graph with an arbitrary density matrix referred to a standard orthonormal basis in the Hilbert space of a finite dimensional quantum system. We study the related issues like classification of…

Quantum Physics · Physics 2007-08-28 Ali Saif M. Hassan , Pramod Joag

Realizing photonic graph states, crucial in various quantum protocols, is challenging due to the absence of deterministic entangling gates in linear optics. To address this, emitter qubits have been leveraged to establish and transfer the…

Quantum Physics · Physics 2024-12-10 Sobhan Ghanbari , Jie Lin , Benjamin MacLellan , Luc Robichaud , Piotr Roztocki , Hoi-Kwong Lo