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Related papers: A measurable entanglement criterion for two qubits

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We provide a novel criterion for identifying quantum correlation, which allows us to find connections between Bell type inequalities, entanglement detection, and correlation. We utilize the criterion to construct witness operators that can…

Quantum Physics · Physics 2007-05-23 Che-Ming Li , Li-Yi Hsu , Wei-Yang Lin , Yueh-Nan Chen , Der-San Chuu , Tobias Brandes

We present separability criteria based on local symmetric measurements. These experimental plausible criteria are shown to be more efficient in detecting entanglement than the current counterparts by detailed examples. Furthermore, we…

Quantum Physics · Physics 2025-12-30 Yu Lu , Hao-Fan Wang , Meng Su , Zhi-Xi Wang , Shao-Ming Fei

We propose an experimental scheme for the measurement of entanglement between two two-level atoms. Our scheme requires one of the two entangled atoms to interact with a cavity field dispersively, and we show that by measuring the zero…

Quantum Physics · Physics 2022-06-29 Nilakantha Meher , M. Bhattacharya , Anand K. Jha

Entanglement is a key ingredient for quantum technologies and a fundamental signature of quantumness in a broad range of phenomena encompassing many-body physics, thermodynamics, cosmology, and life sciences. For arbitrary multiparticle…

Quantum Physics · Physics 2016-10-24 Marco Cianciaruso , Thomas R. Bromley , Gerardo Adesso

The unique entanglement measure is concurrence in a 2-qubit pure state. The maximum violation of Bell's inequality is monotonically increasing for this quantity. Therefore, people expect that pure state entanglement is relevant to the…

Quantum Physics · Physics 2022-12-14 Xingyu Guo , Chen-Te Ma

Separability problem, to decide whether a given state is entangled or not, is a fundamental problem in quantum information theory. We propose a powerful and computationally simple separability criterion, which allows us to detect the…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yong-Sheng Zhang , Shun Zhang , Guang-Can Guo

We give an explicit expression for the geometric measure of entanglement for three qubit states that are linear combinations of four orthogonal product states. It turns out that the geometric measure for these states has three different…

Quantum Physics · Physics 2008-09-03 Levon Tamaryan , DaeKil Park , Jin-Woo Son , Sayatnova Tamaryan

We develop a geometric approach to quantify the capability of creating entanglement for a general physical interaction acting on two qubits. We use the entanglement measure proposed by us for $N$-qubit pure states (PRA \textbf{77}, 062334…

Quantum Physics · Physics 2015-05-13 Behzad Lari , Ali Saif M. Hassan , Pramod S. Joag

Bound entangled states are states that are entangled but from which no entanglement can be distilled if all parties are allowed only local operations and classical communication. However, in creating these states one needs nonzero…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Joseph B. Altepeter , Paul M. Goldbart , William J. Munro

Detection of entanglement through partial knowledge of the quantum state is a challenge to implement efficiently. Here we propose a separability criterion for detecting bipartite entanglement in arbitrary dimensional quantum states using…

Quantum Physics · Physics 2024-05-28 Shruti Aggarwal , Satyabrata Adhikari , A. S. Majumdar

We generalize previously proposed conditions each measure of entanglement has to satisfy. We present a class of entanglement measures that satisfy these conditions and show that the Quantum Relative Entropy and Bures Metric generate two…

Quantum Physics · Physics 2011-07-19 V. Vedral , M. B. Plenio

For a projective measurement, the Born rule provides the probability for an outcome in terms of the inner product between a projector and a quantum state. If the projector represents a pure entangled state and the state for a composite…

Quantum Physics · Physics 2017-03-16 Arun Sehrawat

Measuring entanglement is a demanding task that usually requires full tomography of a quantum system, involving a number of observables that grows exponentially with the number of parties. Recently, it was suggested that adding a single…

We derive tight quadratic inequalities for all kinds of hybrid separable-inseparable $n$-particle density operators on an arbitrary dimensional space. This methodology enables us to truly derive a tight quadratic inequality as tests for…

Quantum Physics · Physics 2009-11-07 Koji Nagata , Masato Koashi , Nobuyuki Imoto

Efficient certification and quantification of high dimensional entanglement of composite systems are challenging both theoretically as well as experimentally. Here, we demonstrate that several entanglement detection methods can be…

Quantum Physics · Physics 2026-01-28 Som Kanjilal , Vivek Pandey , Arun Kumar Pati

This paper is an appendix to a previous paper: quant-ph/0101123 ``Relaxation Method for Calculating Quantum Entanglement", by Robert Tucci. For certain mixtures of Bell basis states, namely the Werner States, we use the theoretical…

Quantum Physics · Physics 2007-05-23 Robert R. Tucci

We find the nearest product states for arbitrary generalized W states of n qubits, and show that the nearest product state is essentially unique if the W state is highly entangled. It is specified by a unit vector in Euclidean n-dimensional…

Quantum Physics · Physics 2010-05-19 Sayatnova Tamaryan , Anthony Sudbery , Levon Tamaryan

We derive several entanglement criteria for bipartite continuous variable quantum systems based on the Shannon entropy. These criteria are more sensitive than those involving only second-order moments, and are equivalent to well-known…

Quantum Physics · Physics 2015-05-14 S. P. Walborn , B. G. Taketani , A. Salles , F. Toscano , R. L. de Matos Filho

We present a concise introduction to quantum entanglement. Concentrating on bipartite systems we review the separability criteria and measures of entanglement. We focus our attention on geometry of the sets of separable and maximally…

Quantum Physics · Physics 2007-05-23 Karol Zyczkowski , Ingemar Bengtsson

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