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Related papers: Unextendible Product Bases and Bound Entanglement

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We investigate the problem of constructing unextendible product bases in the qubit case - that is, when each local dimension equals 2. The cardinality of the smallest unextendible product basis is known in all qubit cases except when the…

Quantum Physics · Physics 2013-11-15 Nathaniel Johnston

We discuss the problem of characterizing upper bounds on entanglement in a bipartite quantum system when only the reduced density matrices (marginals) are known. In particular, starting from the known two-qubit case, we propose a family of…

An analytic proof is given which shows that it is impossible to extend any triple of mutually unbiased (MU) product bases in dimension six by a single MU vector. Furthermore, the 16 states obtained by removing two orthogonal states from any…

Quantum Physics · Physics 2012-10-02 Daniel McNulty , Stefan Weigert

The unambiguous detection and quantification of entanglement is a hot topic of scientific research, though it is limited to low dimensions or specific classes of states. Here we identify an additional class of quantum states, for which…

Quantum Physics · Physics 2014-12-03 Marco Roncaglia , Arianna Montorsi , Marco Genovese

We discuss quantitatively the complementarity of information transmitted by a quantum system prepared in a basis state in one out of several different mutually unbiased bases (MUBs). We obtain upper bounds on the information available to a…

Quantum Physics · Physics 2009-11-13 Shengjun Wu , Sixia Yu , Klaus Mølmer

We systematically study the construction of mutually unbiased bases in $\mathbb{C}^{2}\bigotimes\mathbb{C}^{3}$, such that all the bases are unextendible maximally entangled ones. Necessary conditions of constructing a pair of mutually…

Quantum Physics · Physics 2015-06-23 Halqem Nizamidin , Teng Ma , Shao-Ming Fei

Understanding which entangled states give rise to Bell nonlocality and thus are resourceful in the device-independent framework is a long-stanging unresolved problem. Here we establish the equivalence between genuine entanglement and…

Quantum Physics · Physics 2025-08-26 Owidiusz Makuta , Remigiusz Augusiak

We examine the existence and structure of particular sets of mutually unbiased bases (MUBs) in bipartite qudit systems. In contrast to well-known power-of-prime MUB constructions, we restrict ourselves to using maximally entangled…

Quantum Physics · Physics 2011-09-02 Wim van Dam , Mark Howard

In the present paper, a novel framework to detect genuine multipartite entanglement (GME) has been presented by computing correlations in mutually unbiased bases (MUBs). It has been shown that correlation obtained by measuring in MUBs of…

Quantum Physics · Physics 2025-09-30 Sumit Nandi

In this paper, we mainly study the local indistinguishability of multipartite product states. Firstly, we follow the method of Z.-C. Zhang \emph{et al}[Phys. Rev. A 93, 012314(2016)] to give another more concise set of $2n-1$ orthogonal…

Quantum Physics · Physics 2016-03-08 Yan-Ling Wang , Mao-Sheng Li , Zhu-Jun Zheng , Shao-Ming Fei

Continuous variables multipartite entanglement is a key resource for quantum technologies. This works considers the multipartite entanglement generated in separated spatial modes of the same light beam by three different parametric sources:…

Quantum Physics · Physics 2021-12-08 Alessandra Gatti

The geometric measure of entanglement of a pure quantum state is defined to be its distance to the space of product (seperable) states. Given an $n$-partite system composed of subsystems of dimensions $d_1,\ldots, d_n$, an upper bound for…

Quantum Physics · Physics 2018-05-09 Liqun Qi , Guofeng Zhang , Guyan Ni

Nonlocality without entanglement is an interesting field. A manifestation of quantum nonlocality without entanglement is the local indistinguishability of a set of orthogonal product states. In this paper we analyze the character of…

Quantum Physics · Physics 2009-11-10 Ping Xing Chen , Cheng Zu Li

Understanding what can be inferred about a multi-particle quantum system from only the knowledge of its subparts is a highly non-trivial task. Clearly, if the global system doesn't contain any information resource, nor do its subparts.…

Quantum Physics · Physics 2013-05-30 Lars Erik Würflinger , Jean-Daniel Bancal , Antonio Acín , Nicolas Gisin , Tamas Vertesi

Genuine multipartite entanglement is of great importance in quantum information, especially from the experimental point of view. Nevertheless, it is difficult to construct genuine multipartite entangled states systematically, because the…

Quantum Physics · Physics 2020-03-05 Yi Shen , Lin Chen

We study the fully entangled fraction of a quantum state. An upper bound is obtained for arbitrary bipartite system. This upper bound only depends on the Frobenius norm of the state.

Quantum Physics · Physics 2016-08-03 Xiaofen Huang , Naihuan Jing , Tinggui Zhang

We investigate whether pure entangled states can be associated to a measurement basis in which all vectors are local unitary transformations of the original state. We prove that for bipartite states with a local dimension that is either $2,…

Quantum Physics · Physics 2023-08-28 Florian Pimpel , Martin J. Renner , Armin Tavakoli

We introduce a class of entangled subspaces: completely entangled subspaces of entanglement depth $k$ ($k$-CESs). These are subspaces of multipartite Hilbert spaces containing only pure states with an entanglement depth of at least $k$. We…

Quantum Physics · Physics 2024-07-03 Maciej Demianowicz , Kajetan Vogtt , Remigiusz Augusiak

A long-standing open question asks for the minimum number of vectors needed to form an unextendible product basis in a given bipartite or multipartite Hilbert space. A partial solution was found by Alon and Lovasz in 2001, but since then…

Quantum Physics · Physics 2015-01-07 Jianxin Chen , Nathaniel Johnston

We propose novel mixed states in two qubits, ``maximally entangled mixed states'', which have a property that the amount of entanglement of these states cannot be increased further by applying any unitary operations. The property is proven…

Quantum Physics · Physics 2007-05-23 Satoshi Ishizaka , Tohya Hiroshima