English
Related papers

Related papers: Entanglement in eight-qubit graph states

200 papers

Classification of entanglement in multipartite quantum systems is an open problem solved so far only for bipartite systems and for systems composed of three and four qubits. We propose here a coarse-grained classification of entanglement in…

Combinatorics · Mathematics 2018-08-15 Luigi Seveso , Dardo Goyeneche , Karol Życzkowski

Entanglement plays an important role in quantum communication, algorithms, and error correction. Schmidt coefficients are correlated to the eigenvalues of the reduced density matrix. These eigenvalues are used in Von Neumann entropy to…

Quantum Physics · Physics 2014-09-25 Anmer Daskin , Ananth Grama , Sabre Kais

We classify, up to local unitary equivalence, local unitary stabilizer Lie algebras for symmetric mixed states into six classes. These include the stabilizer types of the Werner states, the GHZ state and its generalizations, and Dicke…

Quantum Physics · Physics 2013-05-29 David W. Lyons , Scott N. Walck

The first characterization of mixed-state entanglement was achieved for two-qubit states in Werner's seminal work [Phys. Rev. A 40, 4277 (1989)]. A physically important extension of this result concerns mixtures of a pure entangled state…

Quantum Physics · Physics 2015-06-15 Christopher Eltschka , Jens Siewert

Towards realising larger scale quantum algorithms, the ability to prepare sizeable multi-qubit entangled states with full qubit control is used as a benchmark for quantum technologies. We investigate the extent to which entanglement is…

Quantum Physics · Physics 2021-01-12 Gary J. Mooney , Charles D. Hill , Lloyd C. L. Hollenberg

We propose a general method for preparing stabilizer states with reduced two-qubit gate count and depth compared to the state of the art. The method starts from a graph state representation of the stabilizer state and iteratively reduces…

The characterization of genuine multiparticle entanglement is important for entanglement theory as well as experimental studies related to quantum information theory. Here, we completely characterize genuine multiparticle entanglement for…

Quantum Physics · Physics 2011-11-28 Otfried Gühne , Bastian Jungnitsch , Tobias Moroder , Yaakov S. Weinstein

As quantum technology advances and the size of quantum computers grow, it becomes increasingly important to understand the extent of quality in the devices. As large-scale entanglement is a quantum resource crucial for achieving quantum…

Quantum Physics · Physics 2024-10-07 John F Kam , Haiyue Kang , Charles D Hill , Gary J Mooney , Lloyd C L Hollenberg

Hypergraph states as real equally weighted pure states are important resources for quantum codes of non-local stabilizer. Using local Pauli equivalence and permutational symmetry, we reduce the 32768 four qubit real equally weighted pure…

Quantum Physics · Physics 2014-10-07 Xiao-yu Chen , Lei Wang

Graph states are computationally powerful quantum states with many applications including use as resource states for measurement-based quantum computing (MBQC). We demonstrate construction of graph states on a Rydberg atom quantum analogue…

Quantum Physics · Physics 2025-04-22 Zhangjie Qin , V. W. Scarola

We consider the Schmidt decomposition of a bipartite density operator induced by the Hilbert-Schmidt scalar product, and we study the relation between the Schmidt coefficients and entanglement. First, we define the Schmidt equivalence…

Quantum Physics · Physics 2009-08-22 Paolo Aniello , Cosmo Lupo

We present an algorithm for efficiently simulating a quantum circuit in the graph formalism. In the graph formalism, we represent states as a linear combination of graphs with Clifford operations on their vertices. We show how a…

Quantum Physics · Physics 2021-08-09 Andrey Boris Khesin , Kevin Ren

Random circuit models often describe local dynamics using generic two-qubit gates, which have proven successful in capturing entanglement growth and operator spreading in many contexts. This approach naturally leads to the expectation that…

We propose a new approach to the geometry of the four-qubit entanglement classes depending on parameters. More precisely, we use invariant theory and algebraic geometry to describe various stratifications of the Hilbert space by SLOCC…

Mathematical Physics · Physics 2017-03-08 Frédéric Holweck , Jean-Garbriel Luque , Jean-Yves Thibon

Gibbs states of an infinite system of interacting quantum particles are considered. Each particle moves on a compact Riemannian manifold and is attached to a vertex of a graph (one particle per vertex). Two kinds of graphs are studied: (a)…

Mathematical Physics · Physics 2009-11-11 D. Kepa , Y. Kozitsky

We describe the structure of the $n$-qubit Clifford group $C_n$ via Cayley graphs, whose vertices represent group elements and edges represent generators. In order to obtain the action of Clifford gates on a given quantum state, we…

Quantum Physics · Physics 2026-05-05 Cynthia Keeler , William Munizzi , Jason Pollack

Certifying entanglement of a multipartite state is generally considered as a demanding task. Since an $N$ qubit state is parametrized by $4^{N}-1$ real numbers, one might naively expect that the measurement effort of generic entanglement…

Quantum Physics · Physics 2016-11-23 Lukas Knips , Christian Schwemmer , Nico Klein , Marcin Wieśniak , Harald Weinfurter

We introduce a mapping between graphs and pure quantum bipartite states and show that the associated entanglement entropy conveys non-trivial information about the structure of the graph. Our primary goal is to investigate the family of…

Quantum Physics · Physics 2012-02-24 Silvano Garnerone , Paolo Giorda , Paolo Zanardi

We study entanglement properties of hypergraph states in arbitrary finite dimension. We compute multipartite entanglement of elementary qudit hypergraph states, namely those endowed with a single maximum-cardinality hyperedge. We show that,…

Quantum Physics · Physics 2022-10-12 Daniele Malpetti , Alfredo Bellisario , Chiara Macchiavello

Measurement based quantum computing is preformed by adding non-Clifford measurements to a prepared stabilizer states. Entangling gates like CZ are likely to have lower fidelities due to the nature of interacting qubits, so when preparing a…

Quantum Physics · Physics 2025-07-29 James Davies , Andrew Jena