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Related papers: Quantum discord of certain two-qubit states

200 papers

In [X.-W. Hou, Z.-P. Huang, S. Chen, Eur. Phys. J. D 68, 1 (2014)], Hou et al. present, using Tsallis' entropy, possible generalizations of the quantum discord measure, finding original results. As for the mutual informations and discord,…

Quantum Physics · Physics 2015-04-09 Guido Bellomo , Angelo Plastino , Anna P. Majtey , Angel R. Plastino

We review the theoretical and the experimental aspects regarding the quantification and identification of quantum correlations in liquid-state nuclear magnetic resonance (NMR) systems at room temperature. We start by introducing a formal…

Several ways have been proposed in the literature to define a coherence measure based on Tsallis relative entropy. One of them is defined as a distance between a state and a set of incoherent states with Tsallis relative entropy taken as a…

Quantum Physics · Physics 2019-12-12 Anna Vershynina

We describe an efficient DQC1-algorithm to quantify the amount of Geometric Quantum Discord present in the output state of a DQC1 computation. DQC1 is a model of computation that utilizes separable states to solve a problem with no known…

Quantum Physics · Physics 2012-07-13 G. Passante , O. Moussa , R. Laflamme

Quantum discord is a prominent measure of quantum correlations, playing an important role in expanding its horizon beyond entanglement. Here we provide an operational meaning of (geometric) discord, which quantifies the amount of…

Quantum Physics · Physics 2015-06-05 Satyabrata Adhikari , Subhashish Banerjee

Correlations are a very important tool in the study of multipartite systems, both for classical and quantum ones. The discussion about the quantum nature of correlations permeates Physics since Einstein, Podolski and Rosen published their…

Quantum Physics · Physics 2011-12-13 Lucas C. Céleri , Jonas Maziero , Roberto M. Serra

We review concepts and methods associated with quantum discord and related topics. We also describe their possible connections with other aspects of quantum information and beyond, including quantum communication, quantum computation,…

Quantum Physics · Physics 2018-01-17 Anindita Bera , Tamoghna Das , Debasis Sadhukhan , Sudipto Singha Roy , Aditi Sen De , Ujjwal Sen

We study analytically the dynamic behaviors of quantum correlation measured by quantum discord between two uncoupled qubits, which are immersed in a common Ohmic environment. We show that the quantum discord of the two noninteracting qubits…

Quantum Physics · Physics 2015-05-19 Ji-Bing Yuan , Jie-Qiao Liao , Le-Man Kuang

We address the experimental determination of entropic quantum discord for systems made of a pair of polarization qubits. We compare results from full and partial tomography and found that the two determinations are statistically compatible,…

In a pair of correlated quantum systems a measurement in one corresponds to a change in the state of the other. In the process, information is lost. Measurement along which set of projectors would accompany minimum loss in information…

Quantum Physics · Physics 2022-05-19 Chitradeep Gupta

Quantum correlation includes quantum entanglement and quantum discord. Both entanglement and discord have a common necessary condition--------quantum coherence or quantum superposition. In this paper, we attempt to give an alternative…

Quantum Physics · Physics 2014-09-23 Chang-shui Yu , Yang Zhang , Haiqing Zhao

The protocol proposed in the commented-upon article can certify zero discord; however, it fails to quantify non-zero discord for some states. Further, the protocol is less efficient than calculating discord via performing full quantum state…

Quantum Physics · Physics 2020-07-27 Parveen Kumar , Kyrylo Snizhko

Quantum discord, a key indicator of non-classical correlations in bipartite systems, has been recently extended to multipartite scenarios [Phys. Rev. Lett. 2020, 124:110401]. We present exact analytic formulas for the quantum discord of…

Quantum Physics · Physics 2025-03-21 Jianming Zhou , Xiaoli Hu , Honglian Zhang , Naihuan Jing

Positivity of quantum discord is shown to be equivalent to the strong sub additivity of the Von-Nuemann entropy. This leads to a connection between the mother protocol of quantum information theory [A. Abeyesinghe, I. Devetak, P. Hayden,…

Quantum Physics · Physics 2011-07-07 Vaibhav Madhok , Animesh Datta

Entanglement is known to be an essential resource for many quantum information processes. However, it is now known that some quantum features may be acheived with quantum discord, a generalized measure of quantum correlation. In this paper,…

For the first time, we compute the quantum discord in bipartite systems containing up to nine qubits. An analytical expression is obtained for the discord in a bipartite system with three qubits. The dependence of the discord on the…

Quantum Physics · Physics 2014-04-08 A. Y. Chernyavskiy , S. I. Doronin , E. B. Fel'dman

One of the best signatures of nonclassicality in a quantum system is the existence of correlations that have no classical counterpart. Different methods for quantifying the quantum and classical parts of correlations are amongst the more…

Quantum Physics · Physics 2012-11-29 Kavan Modi , Aharon Brodutch , Hugo Cable , Tomasz Paterek , Vlatko Vedral

Noisy quantum walks are studied from the perspective of comparing their quantumness as defined by two popular measures, measurement-induced disturbance (MID) and quantum discord (QD). While the former has an operational definition, unlike…

Quantum Physics · Physics 2011-07-01 Balaji R. Rao , R. Srikanth , C. M. Chandrashekar , Subhashish Banerjee

We introduce a measurement-based method for verifying quantum discord of any bipartite quantum system. We show that by performing an informationally complete POVM (IC-POVM) on one subsystem and checking the commutativity of the conditional…

Quantum Physics · Physics 2013-01-23 Saleh Rahimi-Keshari , Carlton M. Caves , Timothy C. Ralph

This paper summarizes the basics of the notion of quantum discord and how it relates to other types of correlations in quantum physics. We take the fundamental information theoretic approach and illustrate our exposition with a number of…

Quantum Physics · Physics 2017-02-07 Vlatko Vedral