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Related papers: Entangled Qubits in a non-Gaussian Quantum State

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We propose a new avenue towards distillation of quantum entanglement that is implemented by directly passing the entangled qubits through a mode-matched filter. This approach can be applied to a common class of entanglement impurities…

Quantum Physics · Physics 2015-05-30 Yu-Ping Huang , Prem Kumar

In this paper, we investigate the possibility of entanglement swapping between two distinct qubits coupled to their own (in general) non-Markovian environments. This is done via Bell state measurement performing on the photons leaving the…

Quantum Physics · Physics 2016-08-31 Alireza Nourmandipour , M. K. Tavassoly

Whether entanglement in a state can be detected, distilled, and quantified without full state reconstruction is a fundamental open problem. We demonstrate a new scheme encompassing these three tasks for arbitrary two-qubit entanglement, by…

Quantum Physics · Physics 2010-12-03 H. S. Park , S. -S. B. Lee , H. Kim , S. -K. Choi , H. -S. Sim

Entanglement distillation is the process of converting noisy entangled states into maximally entangled pure states via local operations and classical communication. A long-standing, unresolved question is which entangled states are amenable…

Quantum Physics · Physics 2026-04-28 Tobias C. Sutter , Christopher Popp , Beatrix C. Hiesmayr

Experimental determination of entanglement is important not only to characterize the state and use it in quantum information, but also in understanding complicated phenomena such as phase transitions. In this paper we show that in many…

Quantum Physics · Physics 2016-01-20 Gaurav Chaudhary , V. Ravishankar

There are several examples of bipartite entangled states of continuous variables for which the existing criteria for entanglement using the inequalities involving the second order moments are insufficient. We derive new inequalities…

Quantum Physics · Physics 2016-08-08 G. S. Agarwal , Asoka Biswas

We classify different classes of entangled states arise in a two-qubit system. Some of these classes are of Bell's state types, while others are of the Werner's state types. The degree of entanglement is quantified for different values of…

Quantum Physics · Physics 2011-05-05 F. N. M. Al-Showaikh , N. Metwally , M. Abdel-Aty

Entanglement is a special feature of the quantum world that reflects the existence of subtle, often non-local, correlations between local degrees of freedom. In topological theories such non-local correlations can be given a very intuitive…

High Energy Physics - Theory · Physics 2020-01-31 D. Melnikov , A. Mironov , S. Mironov , A. Morozov , An. Morozov

One of the most fascinating aspects of quantum networks is their capability to distribute entanglement as a nonlocal communication resource. In a first step, this requires network-ready devices that can generate and store entangled states.…

Quantum entanglement between qudits - the d-dimensional version of qubits - is relevant for advanced quantum information processing and provides deeper insights in the nature of quantum correlations. Encoding qudits in the frequency modes…

Quantum Physics · Physics 2013-10-21 Christof Bernhard , Bänz Bessire , Thomas Feurer , André Stefanov

Entangled states are a key resource in fundamental quantum physics, quantum cryp-tography, and quantum computation [1].To date, controlled unitary interactions applied to a quantum system, so-called "quantum gates", have been the most…

Quantum Physics · Physics 2014-01-27 Y. Lin , J. P. Gaebler , F. Reiter , T. R. Tan , R. Bowler , A. S. Sørensen , D. Leibfried , D. J. Wineland

The development of key devices and systems in quantum information technology, such as entangled particle sources, quantum gates and quantum cryptographic systems, requires a reliable and well-established method for characterizing how well…

In this work we study the production and swapping of non-gaussian multipartite entanglement in a setup containing a parametric amplifier which generates three photons in different modes coupled to three qubits. We prove that the…

Quantum Physics · Physics 2022-02-07 A. Agustí Casado , C. Sabín

Quantum non-Gaussianity, a more potent and highly useful form of nonclassicality, excludes all convex mixtures of Gaussian states and Gaussian parametric processes generating them. Here, for the first time, we conclusively test quantum…

We derive necessary and sufficient inseparability conditions imposed on the variance matrix of symmetric qubits. These constraints are identified by examining a structural parallelism between continuous variable states and two qubit states.…

Quantum Physics · Physics 2007-05-23 A. R. Usha Devi , M. S. Uma , R. Prabhu , A. K. Rajagopal

Entanglement verification and measurement is essential for experimental tests of quantum mechanics and also for quantum communication and information science. Standard methods of verifying entanglement in a bipartite mixed state require…

A scheme for generating an entangled state in a two spin-1/2 system by means of a spin-dependent potential scattering of another qubit is presented and analyzed in three dimensions. The entanglement is evaluated in terms of the concurrence…

Quantum Physics · Physics 2010-04-07 Yuichiro Hida , Hiromichi Nakazato , Kazuya Yuasa , Yasser Omar

We provide an analytical investigation of the pairwise entanglement dynamics for a system, consisting an arbitrary number of qubits dissipating into a common and non-Markovian environment for both weak and strong coupling regimes. In the…

Quantum Physics · Physics 2016-03-23 Alireza Nourmandipour , Mohammad Kazem Tavassoly , Morteza Rafiee

Maximally entangled mixed states are those states that, for a given mixedness, achieve the greatest possible entanglement. For two-qubit systems and for various combinations of entanglement and mixedness measures, the form of the…

The dynamics of an ensemble of identically prepared two-qubit systems is investigated which is subjected to the iteratively applied measurements and conditional selection of a typical entanglement purification protocol. It is shown that the…

Quantum Physics · Physics 2011-09-19 T. Kiss , S. Vymětal , L. D. Tóth , A. Gábris , I. Jex , G. Alber