English
Related papers

Related papers: Geometric measures of quantum correlations: charac…

200 papers

We present a dynamic approach to study the quantum discord and classical correlation. By local filtering operation, the evaluation of quantum discord is closely related to quantum channel and channel capacity. As a consequence, the…

Quantum Physics · Physics 2011-07-25 Mingjun Shi , Fengjian Jiang , Jiangfeng Du

Quantum discord is a measure of the quantumness of correlations. After reviewing its different versions and properties, we apply it to the questions of quantum information processing. First we show that changes in discord in the processed…

Quantum Physics · Physics 2015-03-17 Aharon Brodutch , Alexei Gilchrist , Daniel R. Terno , Christopher J. Wood

The quantum discord is used as measure of quantum correlations for two families of multipartite coherent states. The first family interpolates between generalized GHZ states and generalized Werner states. The second one is an interpolation…

Quantum Physics · Physics 2012-11-01 M. Daoud , R. Ahl Laamara

The geometric discord $\mathcal{D}$ of a state is a measure of the quantumness of the state and the negativity $\mathcal{N}$ is a measure of the entanglement of a state. It was proved by D. Girolami and G. Adesso that for states on…

Quantum Physics · Physics 2019-10-08 Priyabrata Bag , Santanu Dey , Hiroyuki Osaka

The notion of distance defined on the set of states of a composite quantum system can be used to quantify total, quantum and classical correlations in a unifying way. We provide new closed formulae for classical and total correlations of…

Quantum Physics · Physics 2014-09-25 Thomas R. Bromley , Marco Cianciaruso , Rosario Lo Franco , Gerardo Adesso

We consider the evaluation of the quantum discord and other related measures of quantum correlations in a system formed by a spin 1 and a complementary spin system. A characterization of general projective measurements in such system in…

Quantum Physics · Physics 2015-06-05 R. Rossignoli , J. M. Matera , N. Canosa

We propose a measure of non-classical correlations in bipartite quantum states based on local unitary operations. We prove the measure is non-zero if and only if the quantum discord is non-zero; this is achieved via a new characterization…

Quantum Physics · Physics 2013-06-25 Sevag Gharibian

In this didactic article we explore the concept of quantum correlations beyond entanglement. We begin by introducing and motivating the classically correlated states and then showing how to quantify the quantum correlations using an…

Quantum Physics · Physics 2016-11-08 Gerardo Adesso , Marco Cianciaruso , Thomas R. Bromley

We propose a scheme to directly measure the exact value of geometric quantum discord of an arbitrary two-qubit state. We only need to perform the projective measurement in the all anti-symmetric subspace and our scheme is parametrically…

Quantum Physics · Physics 2012-03-05 Jia-sen Jin , Feng-yang Zhang , Chang-shui Yu , He-shan Song

We examine the quantum correlations of spin pairs in the ground state of finite XY chains in a transverse field, by evaluating the quantum discord as well as other related entropic measures of quantum correlations. A brief review of the…

Quantum Physics · Physics 2013-12-16 N. Canosa , L. Ciliberti , R. Rossignoli

We consider quantum correlations and quantum discord phenomena for two-qubit states with $X$-type density matrices in the tomographic framework of quantum mechanics. By introducing different measurements schemes, we establish the relation…

Quantum Physics · Physics 2015-04-08 A. K. Fedorov , E. O. Kiktenko , O. V. Man'ko , V. I. Man'ko

We discuss the problem of the separation of total correlations in a given quantum state into entanglement, dissonance, and classical correlations using the concept of relative entropy as a distance measure of correlations. This allows us to…

Quantum Physics · Physics 2010-03-03 Kavan Modi , Tomasz Paterek , Wonmin Son , Vlatko Vedral , Mark Williamson

While entanglement is a cornerstone of quantum theory and holography, quantum correlations arising from superposition, such as quantum discord, offer a broader perspective that has remained largely unexplored in holography. We construct…

High Energy Physics - Theory · Physics 2026-02-11 Takato Mori

We identify ambiguities in the available frameworks for defining quantum, classical, and total correlations as measured by discordlike quantifiers. More specifically, we determine situations for which either classical or quantum…

Quantum Physics · Physics 2014-12-10 F. M. Paula , A. Saguia , Thiago R. de Oliveira , M. S. Sarandy

The effect of quantum steering arises from the judicious combination of an entangled state with a set of incompatible measurements. Recently, it was shown that this form of quantum correlations can be quantified in terms of a dimension,…

In quantum physics, multiparticle systems are described by quantum states acting on tensor products of Hilbert spaces. This product structure leads to the distinction between product states and entangled states; moreover, one can quantify…

Quantum Physics · Physics 2026-03-06 Lisa T. Weinbrenner , Albert Rico , Kenneth Goodenough , Xiao-Dong Yu , Otfried Gühne

Quantum discord (QD) reveals the nonclassical nature of correlations in bipartite quantum states, going beyond the entanglement-separability paradigm. In this article we discuss the suitability of QD in what concern its possible asymmetry…

Quantum Physics · Physics 2015-03-14 J. Maziero , L. C. Celeri , R. M. Serra

We studied the geometric quantum discord of a quantum system consisted of a Jaynes- Cummings atom, a cavity and an isolated atom. The analytical expressions of the geometric quantum discord for two atoms, every atom with cavity and the…

Quantum Physics · Physics 2015-05-01 Wen-Chao Qiang , Lei Zhang , Hua-Ping Zhang

Among various definitions of quantum correlations, quantum discord has attracted considerable attention. To find analytical expression of quantum discord is an intractable task. In this paper, we discuss thoroughly the case of two-qubit…

Quantum Physics · Physics 2015-05-28 Mingjun Shi , Wei Yang , Fengjian Jiang , Jiangfeng Du

Quantum Discord (QD) is a measure of the total quantum non-local correlations of a quantum system. The formalism of quantum discord has been applied to various two-qubit mixed states and it has been reported that there is a non-zero quantum…

Quantum Physics · Physics 2022-10-04 M. S. Ramkarthik , Devvrat Tiwari , Pranay Barkataki