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Related papers: Gaussian geometric discord

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A generalization of the geometric measure of quantum discord is introduced in this article, based on Hellinger distance. Our definition has virtues of computability and independence of local measurement. In addition it also does not suffer…

Quantum Physics · Physics 2016-02-02 Hai-Tao Cui , Jun-Long Tian , Gui Yang

We consider the geometric global quantum discord (GGQD) of two-qubit systems. By analyzing the symmetry of geometric global quantum discord we give an approach for deriving analytical formulae of the extremum problem which lies at the core…

Quantum Physics · Physics 2016-02-18 Yunlong Xiao , Tao Li , Shao-Ming Fei , Naihuan Jing , Xianqing Li-Jost , Zhi-Xi Wang

We extend the quantum discord to continuous variable systems and evaluate Gaussian quantum discord C(\rho) for bipartite Gaussian states. In particular, for squeezed thermal states (STS), we explicitly maximize the extractable information…

Quantum Physics · Physics 2015-05-18 Paolo Giorda , Matteo G. A. Paris

Two geometric measures for quantum discord were recently proposed by Modi et al. [Phys. Rev. Lett. 104, 080501 (2010)] and Dakic et al. [Phys. Rev. Lett. 105, 190502 (2010)]. We study the similarities and differences for total quantum…

Quantum Physics · Physics 2011-09-09 Zhenyu Xu , Wanli Yang , Xing Xiao , Mang Feng

Radhakrishnan \emph{et.al} [Phys. Rev. Lett. \textbf{124}, 110401 (2020)] proposed quantum discord to multipartite systems and derived explicit formulae for any states. These results are significant in capturing quantum correlations for…

Quantum Physics · Physics 2021-07-01 Chen-Lu Zhu , Bin Hu , Bo Li , Zhi-Xi Wang , Shao-Ming Fei

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

We give the explicit expressions of the pairwise quantum correlations present in superpositions of multipartite coherent states. A special attention is devoted to the evaluation of the geometric quantum discord. The dynamics of quantum…

Quantum Physics · Physics 2015-06-11 M. Daoud , R. Ahl Laamara

The minimal Bures distance of a quantum state of a bipartite system AB to the set of classical states for subsystem A defines a geometric measure of quantum discord. When A is a qubit, we show that this geometric quantum discord is given in…

Quantum Physics · Physics 2013-12-24 Dominique Spehner , Miguel Orszag

The dynamics of a geometric measure of the quantum discord (GMQD) under decoherence is investigated. We show that the GMQD of a two-qubit state can be alternatively obtained through the singular values of a $3\times4$ matrix whose elements…

Quantum Physics · Physics 2010-09-07 Xiao-Ming Lu , Zheng-Jun Xi , Zhe Sun , Xiaoguang Wang

Composite quantum systems can be in generic states characterized not only by entanglement, but also by more general quantum correlations. The interplay between these two signatures of nonclassicality is still not completely understood. In…

Quantum Physics · Physics 2011-11-17 Davide Girolami , Gerardo Adesso

We define a new measure of quantum correlations in bipartite quantum systems given by the Bures distance of the system state to the set of classical states with respect to one subsystem, that is, to the states with zero quantum discord. Our…

Quantum Physics · Physics 2013-12-23 Dominique Spehner , Miguel Orszag

The geometric quantum discord of a two-qudit state has been studied in many papers, however, its exact analytical value in the explicit form is known only for a general two-qubit state, a general qubit-qudit state and some special families…

Quantum Physics · Physics 2024-09-24 Elena R. Loubenets , Louis Hanotel

We propose a modified metric based on the Hilbert-Schmidt norm and adopt it to define a rescaled version of the geometric measure of quantum discord. Such a measure is found not to suffer from the pathological dependence on state purity.…

Quantum Physics · Physics 2013-06-21 Tommaso Tufarelli , Tom MacLean , Davide Girolami , Ruggero Vasile , Gerardo Adesso

We investigate the level surfaces of geometric measure of quantum discord, and provide a pictorial interpretation of geometric discord for Bell-diagonal states. We have observed its nonanalytic behavior under decoherence employing this…

Quantum Physics · Physics 2013-03-21 Yao Yao , Hong-Wei Li , Zhen-Qiang Yin , Zheng-Fu Han

We introduce a geometric quantification of quantum coherence in single-mode Gaussian states and we investigate the behavior of distance measures as functions of different physical parameters. In the case of squeezed thermal states, we…

Quantum discord is an optimal resource for the quantification of classical and non-classical correlations as compared to other related measures. Geometric measure of quantum discord is another measure of quantum correlations. Recently, the…

Quantum Physics · Physics 2013-08-06 M. Ramzan

Quantum discord quantifies the total non-classical correlations in mixed states. It is the difference between total correlation, measured by quantum mutual information, and the classical correlation. Another step forward towards the…

Quantum Physics · Physics 2013-11-19 M. Ramzan

Quantum correlations may be measured by means of the distance of the state to the subclass of states $\Omega$ having well defined classical properties. In particular, a geometric measure of asymmetric discord [Dakic et al., Phys. Rev. Lett.…

Quantum Physics · Physics 2012-12-06 Adam Miranowicz , Pawel Horodecki , Ravindra W. Chhajlany , Jan Tuziemski , Jan Sperling

A symmetric measure of quantum correlation based on the Hilbert-Schmidt distance is presented in this paper. For two-qubit states, we simplify considerably the optimization procedure so that numerical evaluation can be performed…

Quantum Physics · Physics 2011-07-18 Mingjun Shi , Fengjian Jiang , Jiangfeng Du

We study quantum correlations beyond entanglement in two-mode Gaussian states of continuous variable systems, by means of the measurement-induced disturbance (MID) and its ameliorated version (AMID). In analogy with the recent studies of…

Quantum Physics · Physics 2015-03-17 Ladislav Mišta, , Richard Tatham , Davide Girolami , Natalia Korolkova , Gerardo Adesso