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Related papers: Symmetric entanglement classes for n qubits

200 papers

We have devised an artificial intelligence algorithm with machine reinforcement learning (Q-learning) to construct remarkable entangled states with 4 qubits. This way, the algorithm is able to generate representative states for some of the…

Quantum Physics · Physics 2025-08-08 Sara Giordano , Miguel A. Martin-Delgado

We investigate multiqubit permutation-symmetric states with maximal entropy of entanglement. Such states can be viewed as particular spin states, namely anticoherent spin states. Using the Majorana representation of spin states in terms of…

Quantum Physics · Physics 2015-12-01 D. Baguette , F. Damanet , O. Giraud , J. Martin

With an easily applicable criterion based on permutation symmetries of (identically prepared) replicas of quantum states we identify distinct entanglement classes in high-dimensional multi- partite systems. The different symmetry properties…

Quantum Physics · Physics 2015-05-30 Florian Mintert , Benno Salwey , Andreas Buchleitner

We give a fermionic Fock space description of embedded entangled qubits. Within this framework the problem of classification of pure state entanglement boils down to the problem of classifying spinors. The usual notion of separable states…

Quantum Physics · Physics 2015-07-01 Péter Lévay , Fréderic Holweck

In this paper, building on some recent progress combined with numerical techniques, we shed some new light on how the nonlocality of symmetric states is related to their entanglement properties and potential usefulness in quantum…

Quantum Physics · Physics 2013-01-07 Zizhu Wang , Damian Markham

For pure symmetric 3-qubit states there are only three algebraically independent entanglement measures; one choice is the pairwise concurrence $\mathcal C$, the 3-tangle $\tau$, and the Kempe invariant $\kappa$. Using a canonical form for…

Quantum Physics · Physics 2017-12-13 Alexander Meill , David A. Meyer

We consider a quantum system of n qudits and the Clebsch-Gordan decomposition of the associated Hilbert space. In this decomposition, one of the subspaces is the so-called symmetric subspace or symmetric sector, that is, the subspace of all…

Quantum Physics · Physics 2025-07-09 Domenico D'Alessandro

We undertake experimental detection of the entanglement present in arbitrary three-qubit pure quantum states on an NMR quantum information processor. Measurements of only four observables suffice to experimentally differentiate between the…

Quantum Physics · Physics 2018-09-06 Amandeep Singh , Harpreet Singh , Kavita Dorai , Arvind

We show that a positive homogeneous function that is invariant under determinant-1 stochastic local operations and classical communication (SLOCC) transformations defines an N-qubit entanglement monotone if and only if the homogeneous…

Quantum Physics · Physics 2013-05-30 Christopher Eltschka , Thierry Bastin , Andreas Osterloh , Jens Siewert

Based on results well known in the mathematics literature but have not made their debut to the physics literature yet we conduct a study on three-fermionic systems with six, seven, eight and nine single-particle states. Via introducing…

Quantum Physics · Physics 2014-04-17 Gábor Sárosi , Péter Lévay

It has been shown by Versraete et. al [F. Versraete, J. Dehaene, B. De Moor, and H. Verschelde, Phys. Rev. A65, 052112 (2002)] that by stochastic local operations and classical communication (SLOCC), a pure state of four qubits can be…

Quantum Physics · Physics 2010-08-06 S. Shelly Sharma , N. K. Sharma

We show that for tripartite quantum pure states of qubits, all the kinds of entanglement in terms of SLOCC classification are experimentally measurable by simple projective measurements, provided that four copies of the composite quantum…

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

We generalize the Majorana stellar representation of spin-$s$ pure states to mixed states, and in general to any hermitian operator, defining a bijective correspondence between three spaces: the spin density-matrices, a projective space of…

Quantum Physics · Physics 2020-03-04 E. Serrano-Ensástiga , D. Braun

So far, various multi-photon entangled states have been observed experimentally by using different experimental set-ups. Here, we present a scheme to realize many SLOCC-inequivalent states of three and four qubits via projective…

Quantum Physics · Physics 2009-02-17 Witlef Wieczorek , Nikolai Kiesel , Christian Schmid , Harald Weinfurter

The stabilizer group of an n-qubit state \psi is the set of all matrices of the form g=g_1\otimes\cdots\otimes g_n, with g_1,...,g_n being any 2x2 invertible complex matrices, that satisfy g\psi=\psi. We show that for 5 or more qubits,…

Quantum Physics · Physics 2017-12-06 Gilad Gour , Barbara Kraus , Nolan R. Wallach

Quantum states are represented by positive semidefinite Hermitian operators with unit trace, known as density matrices. An important subset of quantum states is that of separable states, the complement of which is the subset of…

Mathematical Physics · Physics 2020-12-04 Grigoriy Blekherman , H. M. Bharath

We studied pure state transformations using local operations assisted by finitely many rounds of classical communication ($LOCC_{\mathbb{N}}$) in C. Spee, J.I. de Vicente, D. Sauerwein, B. Kraus, arXiv:1606.04418 (2016). Here, we first of…

Quantum Physics · Physics 2017-02-01 J. I. de Vicente , C. Spee , D. Sauerwein , B. Kraus

Entanglement properties of a basic set of eight entangled three particle pure states possessing certain permutation symmetries are studied. They fall into four sets of two entangled states, differing in their patterns of robustness to…

Quantum Physics · Physics 2009-11-07 A. K. Rajagopal , R. W. Rendell

We investigate the physically allowed probabilities for transforming one N-partite W-class state to another by means of local operations assisted with classical communication (LOCC). Recently, Kintas and Turgut have obtained an upper bound…

Quantum Physics · Physics 2011-08-16 Wei Cui , Eric Chitambar , Hoi-Kwong Lo

Entanglement is a resource to overcome the natural restriction of operations used for state manipulation to Local Operations assisted by Classical Communication (LOCC). Hence, a bipartite maximally entangled state is a state which can be…

Quantum Physics · Physics 2016-05-20 C. Spee , J. I. de Vicente , B. Kraus