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Related papers: Operational interpretations of quantum discord

200 papers

We use quantum discord to characterize the correlations present in the quantum computational model DQC1, introduced by Knill and Laflamme [Phys. Rev. Lett. 81, 5672 (1998)]. The model involves a collection of qubits in the completely mixed…

Quantum Physics · Physics 2009-11-13 Animesh Datta , Anil Shaji , Carlton M. Caves

Quantum discord refers to an important aspect of quantum correlations for bipartite quantum systems. In our earlier works we have shown that corresponding to every graph (combinatorial) there are quantum states whose properties are…

Quantum Physics · Physics 2019-03-20 Supriyo Dutta , Bibhas Adhikari , Subhashish Banerjee

Criteria of measure quantifying quantum coherence, a unique property of quantum system, are proposed recently. In this paper, we first give an uncertainty-like expression relating the coherence and the entropy of quantum system. This…

Quantum Physics · Physics 2015-07-15 Zhengjun Xi , Yongming Li , Heng Fan

Quantum discord is usually referred to as a measure for quantum correlations. In the search of the fundamental resource to gain a quantum advantage in quantum information applications, quantum discord is considered a promising candidate. In…

Quantum Physics · Physics 2012-06-04 Manuel Gessner , Elsi-Mari Laine , Heinz-Peter Breuer , Jyrki Piilo

Quantum metrology exploits quantum mechanical laws to improve the precision in estimating technologically relevant parameters such as phase, frequency, or magnetic fields. Probe states are usually tailored on the particular dynamics whose…

Top quarks have been recently shown to be a promising system to study quantum information at the highest-energy scale available. The current lines of research mostly discuss topics such as entanglement, Bell nonlocality or quantum…

Quantum Physics · Physics 2023-06-07 Yoav Afik , Juan Ramón Muñoz de Nova

In quantum mechanics, observing is not a passive act. Consider a system of two quantum particles A and B: if a measurement apparatus M is used to make an observation on B, the overall state of the system AB will typically be altered. When…

Quantum Physics · Physics 2014-04-09 Gerardo Adesso , Vincenzo D'Ambrosio , Eleonora Nagali , Marco Piani , Fabio Sciarrino

Quantum correlations have fundamental and technological interest, and hence many measures have been introduced to quantify them. Some hierarchical orderings of these measures have been established, e.g., discord is bigger than entanglement,…

Quantum Physics · Physics 2015-06-04 Patrick J. Coles

Local unitary operations allow for a unifying approach to the quantification of quantum correlations among the constituents of a bipartite quantum system. For pure states, the distance between a given state and its image under…

Quantum Physics · Physics 2015-10-23 M. Cianciaruso , S. M. Giampaolo , W. Roga , G. Zonzo , M. Blasone , F. Illuminati

The ability to distribute quantum entanglement is a prerequisite for many fundamental tests of quantum theory and numerous quantum information protocols. Two distant parties can increase the amount of entanglement between them by means of…

Quantum Physics · Physics 2012-08-24 T. K. Chuan , J. Maillard , K. Modi , T. Paterek , M. Paternostro , M. Piani

We study the nonclassical correlations in a two-qubit state by the perturbing local unitary operation method. We find that the definitions of various non-classicalities including quantum discord (QD), measurement-induced nonlocality (MIN)…

Quantum Physics · Physics 2015-06-23 Jun Zhang , Yang Zhang , Shao-xiong Wu , Chang-shui Yu

Quantum discord, a kind of quantum correlation, is defined as the difference between quantum mutual information and classical correlation in a bipartite system. It has been discussed so far for small systems with only a few independent…

Quantum Physics · Physics 2012-04-26 sai vinjanampathy , A. R. P. Rau

We address the question of the role of quantum correlations beyond entanglement in context of quantum magnetometry. To this end, we study the evolution of the quantum discord, measured by the rescaled discord, of two electron-spin qubits…

Quantum Physics · Physics 2015-06-12 Paweł Mazurek , Katarzyna Roszak , Paweł Horodecki

Gaussian quantum discord is a measure of quantum correlations in Gaussian systems. Using Gaussian discord we quantify the quantum correlations of a bipartite entangled state and a separable two-mode mixture of coherent states. We…

Quantum Physics · Physics 2012-08-13 Lars S. Madsen , Adriano Berni , Mikael Lassen , Ulrik L. Andersen

Quantum discord is an important measure of quantum correlations that can serve as a resource for certain types of quantum information processing. \ Like entanglement, discord is subject to destruction by external noise. The routes by which…

Quantum Physics · Physics 2013-10-22 Nga T. T. Nguyen , Robert Joynt

In this paper, we present the concept of the one-way unlocalizable quantum discord and investigate its properties. We provide a polygamy inequality for it in tripartite pure quantum system of arbitrary dimension. Several tradeoff relations…

Quantum Physics · Physics 2013-05-30 Zhengjun Xi , Heng Fan , Yongming Li

Quantum correlation lies at the very heart of almost all the non-classical phenomena exhibited by quantum systems composed of more than one subsystem. In the recent days it has been pointed out that there exists quantum correlation, namely…

Quantum Physics · Physics 2015-04-17 Prasenjit Deb , Manik Banik

The benefits of entanglement can outlast entanglement itself. In quantum illumination, entanglement is employed to better detect reflecting objects in environments so noisy that all entanglement is destroyed. Here, we show that quantum…

Quantum Physics · Physics 2016-04-20 Christian Weedbrook , Stefano Pirandola , Jayne Thompson , Vlatko Vedral , Mile Gu

We investigate the distribution property of one way discord in multipartite system by introducing the concept of polygamy deficit for one way discord. The difference between one way discord and quantum discord is analogue to the difference…

Quantum Physics · Physics 2016-08-18 Si-Yuan Liu , Yu-Ran Zhang , Wen-Li Yang , Heng Fan

It is shown that a choice of degrees of freedom of a bipartite continuous variable system determines amount of non-classical correlations (quantified by discord) in the system's state. Non-classical correlations (that include entanglement…

Quantum Physics · Physics 2013-04-01 M. Dugic , M. Arsenijevic , J. Jeknic-Dugic