English
Related papers

Related papers: Trade-off relations on CHSH tests for multi-qubit …

200 papers

We propose an explicit formula for an entanglement measure of pure multipartite quantum states, then study a general pure tripartite state in detail, and at end we give some simple but illustrative examples on four-qubits and m-qubits…

Quantum Physics · Physics 2016-08-16 Hoshang Heydari , Gunnar Björk

A complementarity relation is established between the capacity of multiport classical information transmission via quantum states and multiparty quantum correlation measures for three-qubit pure states. The multiparty quantum correlation…

Quantum Physics · Physics 2013-04-02 Rabindra Nepal , R. Prabhu , Aditi Sen De , Ujjwal Sen

A necessary and sufficient entanglement criterion based on variances of Mermin-Klyshko's Bell operators is proved for multiqubit pure states. Contrary to Bell's inequalities, entangled pure states strictly satisfy a quadratic inequality but…

Quantum Physics · Physics 2015-06-26 Zeqian Chen , Quanhua Xu

Quantum-mechanical incompatibility, which precludes the simultaneous precise measurement of non-commuting observables, imposes fundamental limits on the rate at which classical information can be extracted. While the potential to surpass…

We analyze and show experimental results of the conditional purity, the quantum discord and other related measures of quantum correlation in mixed two-qubit states constructed from a pair of photons in identical polarization states. The…

Quantum Physics · Physics 2016-11-23 L. Rebón , R. Rossignoli , J. J. M. Varga , N. Gigena , N. Canosa , C. Iemmi , S. Ledesma

Quantum coherence is the most fundamental of all quantum quantifiers, underlying other well-known quantities such as entanglement, quantum discord, and Bell correlations. It can be distributed in a multipartite system in various ways -- for…

By establishing CHSH operators and CHSH-type inequalities, we show that any entangled pure state in infinite-dimensional systems is entangled in a $2\otimes2$ subspace. We find that, for infinite-dimensional systems, the corresponding…

Quantum Physics · Physics 2013-08-16 Yu Guo

We derive a tight and saturable monogamy relation for three-qubit pure states that bounds the sum of concurrence and concurrence of assistance by the entanglement with an external qubit. The bound decreases strictly with increasing external…

Quantum Physics · Physics 2026-04-21 Limin Gao , Chenxiao Wang

We propose an entanglement tensor to compute the entanglement of a general pure multipartite quantum state. We compare the ensuing tensor with the concurrence for bipartite state and apply the tensor measure to some interesting examples of…

Quantum Physics · Physics 2016-08-16 Hoshang Heydari , Gunnar Björk

Entanglement in incoherent mixtures of pure states of two qubits is considered via the concurrence measure. A set of pure states is optimal if the concurrence for any mixture of them is the weighted sum of the concurrences of the generating…

Quantum Physics · Physics 2011-08-11 K. V. Shuddhodan , M. S. Ramkarthik , Arul Lakshminarayan

We investigate the norms of the Bloch vectors for any quantum state with subsystems less than or equal to four. Tight upper bounds of the norms are obtained, which can be used to derive tight upper bounds for entanglement measure defined by…

Quantum Physics · Physics 2019-03-27 Ming Li , Zong Wang , Jing Wang , Shuqian Shen , Shao-ming Fei

Device-independent certification, also known as self-testing, aims at guaranteeing the proper functioning of untrusted and uncharacterized devices. For example, the quality of an unknown source expected to produce two-qubit maximally…

Quantum Physics · Physics 2022-04-08 Xavier Valcarce , Julian Zivy , Nicolas Sangouard , Pavel Sekatski

We report on experimental studies on entanglement quantification and verification based on uncertainty relations for systems consisting of two qubits. The new proposed measure is shown to be invariant under local unitary transformations, by…

Quantum Physics · Physics 2007-05-23 Zhi-Wei Wang , Yun-Feng Huang , Xi-Feng Ren , Yong-Sheng Zhang , Guang-Can Guo

A complete analysis of entangled triqubit pure states is carried out based on a new simple entanglement measure. An analysis of all possible extremally entangled pure triqubit states with up to eight terms is shown to reduce, with the help…

Quantum Physics · Physics 2007-05-23 Feng Pan , Dan Liu , Guoying Lu , J. P. Draayer

Self-testing allows classical referees to verify the quantum behaviour of some untrusted devices. Recently we developed a framework for building large self-tests by repeating a smaller self-test many times in parallel. However, the…

Quantum Physics · Physics 2017-02-13 Matthew McKague

Recently, Fan \textit{et al.} [Mod. Phys. Lett. A 36, 2150223 (2021)], presented a generalized Clauser-Horne-Shimony-Holt (CHSH) inequality, to identify $N$-qubit Greenberger-Horne-Zeilinger (GHZ) states. They showed an interesting…

Quantum Physics · Physics 2022-06-09 Gang-Gang He , Xing-Yan Fan , Fu-Lin Zhang

In this paper, the CHSH quantum game is extended to four players. This is achieved by exploring all possible 4-variable Boolean functions to identify those that yield a game scenario with a quantum advantage using a specific entangled…

Quantum Physics · Physics 2024-11-26 Joaquim Jusseau , Hamza Jaffali , Frédéric Holweck

Linear measurements are widely applied in sensing classical signals, e.g., gravitational wave (GW), and are developing toward joint measurement of multiple parameters. In this Letter, we aim at multiparameter linear measurements to…

Quantum Physics · Physics 2026-04-13 Guolong Li , Xiao-Ming Lu

We show that the third-order negativity provides a necessary and sufficient criterion for full separability of tripartite pure states, and extend this to mixed states beyond bipartite diagnostics such as negativity. As a minimal nontrivial…

Quantum Physics · Physics 2026-05-12 Chen-Te Ma , Ma-Ke Yuan

For a tripartite pure state of three qubits, it is well known that there are two inequivalent classes of genuine tripartite entanglement, namely the GHZ-class and the W-class. Any two states within the same class can be transformed into…

Quantum Physics · Physics 2015-05-14 Wei Cui , Wolfram Helwig , Hoi-Kwong Lo