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Related papers: Homological analysis of multi-qubit entanglement

200 papers

We characterize the entanglement contained in a pure three-qubit state via operational entanglement measures. To this end we derive a new decomposition for arbitrary 3-qubit states which is characterized by five parameters (up to local…

Quantum Physics · Physics 2012-02-09 J. I. de Vicente , T. Carle , C. Streitberger , B. Kraus

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

Symmetric quantum states are fascinating objects. They correspond to multipartite systems that remain invariant under particle permutations. This symmetry is reflected in their compact mathematical characterisation but also in their unique…

Quantum Physics · Physics 2025-07-15 Carlo Marconi , Guillem Müller-Rigat , Jordi Romero-Pallejà , Jordi Tura , Anna Sanpera

We introduce an entanglement-related quantity that we call the binegativity. Based on numerical evidence, we conjecture that the binegativity is an entanglement measure for two-qubit states. The binegativity is compared to the concurrence…

Quantum Physics · Physics 2017-02-13 Mark W. Girard , Gilad Gour

This article proposes an efficient way of calculating the geometric measure of entanglement using tensor decomposition methods. The connection between these two concepts is explored using the tensor representation of the wavefunction.…

Quantum Physics · Physics 2017-06-13 Peiyuan Teng

We show that restricted shareability of multi-qubit entanglement can be fully characterized by unified-$(q,s)$ entropy. We provide a two-parameter class of bipartite entanglement measures, namely unified-$(q,s)$ entanglement with its…

Quantum Physics · Physics 2011-06-22 Jeong San Kim , Barry C. Sanders

We generate and characterise entangled states of a register of 20 individually controlled qubits, where each qubit is encoded into the electronic state of a trapped atomic ion. Entanglement is generated amongst the qubits during the…

Entanglement is a fundamental aspect of quantum physics, both conceptually and for its many applications. Classifying an arbitrary multipartite state as entangled or separable -- a task referred to as the separability problem -- poses a…

We present a new measure of entanglement for mixed states. It can be approximately computable for every state and can be used to quantify all different types of multipartite entanglement. We show that it satisfies the usual properties of a…

Quantum Physics · Physics 2007-05-23 Fernando G. S. L. Brandao , Reinaldo O. Vianna

We investigate multipartite entanglement via the statistical properties of pure quantum states of n-qubits. By analyzing the distribution of purity among balanced bipartitions, we compare Haar-typical states, uniformly distributed on the…

We characterize the multipartite entanglement of a system of n qubits in terms of the distribution function of the bipartite purity over balanced bipartitions. We search for maximally multipartite entangled states, whose average purity is…

Quantum Physics · Physics 2015-03-13 P. Facchi , G. Florio , U. Marzolino , G. Parisi , S. Pascazio

Quantum mechanics allows systems to be entangled with each other, which results in stronger than classical correlations. Many methods of identifying entanglement have been proposed over years, most of which are based on violating some…

Quantum Physics · Physics 2014-12-31 Ramij Rahaman , Marcin Wieśniak , Marek Żukowski

We study the quantum separability problem by using general symmetric informationally complete measurements and present separability criteria for both $d$-dimensional bipartite and multipartite systems. The criterion for bipartite quantum…

Quantum Physics · Physics 2015-06-09 Bin Chen , Tao Li , Shao-Ming Fei

While entanglement plays an important role in characterizing quantum many-body systems, it is hardly possible to directly access many-body entanglement in real experiments. In this paper, we study how bipartite entanglement of many-body…

Quantum Physics · Physics 2018-07-11 Chae-Yeun Park , Jaeyoon Cho

Multipartite entanglement constitutes one of the key resources in quantum information processing. We exploit correlation tensor norms to develop a framework for its experimental detection without the need for shared frames of reference. By…

Quantum Physics · Physics 2015-05-01 Claude Klöckl , Marcus Huber

We study the separability of symmetric bipartite quantum states and show that a single correlation measurement is sufficient to detect the entanglement of any bipartite symmetric state with a non-positive partial transpose. We also discuss…

Quantum Physics · Physics 2010-02-24 Geza Toth , Otfried Gühne

We introduce a class of mixed multiqubit states, that corresponds to a randomized version of graph states. Such states arise when a graph state is prepared with noisy or imperfect controlled-Z gates. We study the entanglement features of…

We consider physical Hamiltonians that can be represented by the multiparametric Gaussian ensembles, theoretically derive the state ensembles for its eigenstates and analyze the effect of varying system conditions on its bipartite…

Quantum Physics · Physics 2026-04-14 Devanshu Shekhar , Pragya Shukla

The Schmidt coefficients capture all entanglement properties of a pure bipartite state and therefore determine its usefulness for quantum information processing. While the quantification of the corresponding properties in mixed states is…

Quantum Physics · Physics 2019-04-08 Gael Sentís , Christopher Eltschka , Otfried Gühne , Marcus Huber , Jens Siewert

Quantum entanglement between an arbitrary number of remote qubits is examined analytically. We show that there is a non-probabilistic way to address in one context the management of entanglement of an arbitrary number of mixed-state qubits…

Quantum Physics · Physics 2015-02-02 S. M. Hashemi Rafsanjani , J. H. Eberly