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Related papers: Quantum Discord for multiqubit Systems

200 papers

We perform an experimental investigation of Quantum Discord with Spin-Orbit X-states. These states are prepared through the incoherent superposition of different laser beans, where a two-level system is encoded in polarization and the…

Quantum Physics · Physics 2023-12-29 V. S. Lamego , D. G. Braga , W. F. Balthazar , J. A. O. Huguenin

We report a study on the zero-temperature quantum discord as a measure of two-spin correlation of a transverse XY spin chain following a quench across a quantum critical point and investigate the behavior of mutual information, classical…

Statistical Mechanics · Physics 2021-02-15 Tanay Nag , Ayoti Patra , Amit Dutta

We extend the definition of quantum discord as a quantifier of nonClassical correlations in a quantum state to the case where weak measurements are performed on subsystem $A$ of a bipartite system $AB$. The properties of weak discord are…

Quantum Physics · Physics 2015-12-01 Lekshmi S , N Shaji , Anil Shaji

We study the quantum discord (QD) and the classical correlations (CC) in a reference model for strongly correlated electrons, the one-dimensional bond-charge extended Hubbard model. We show that the comparison of QD and CC and of their…

Quantum Physics · Physics 2013-05-29 Michele Allegra , Paolo Giorda , Arianna Montorsi

We show that a local channel cannot create quantum discord (QD) for zero QD states of size $d\geq3$ if and only if either it is a completely decohering channel or it is a nontrivial isotropic channel. For the qubit case this propertiy is…

Quantum Physics · Physics 2013-04-01 Yu Guo , Jinchuan Hou

Quantum discord is significant in analyzing quantum nonclassicality beyond the paradigm of entanglement. Presently we have explored the effectiveness of global unitary operations in manifesting quantum discord from a general two qubit zero…

Quantum Physics · Physics 2021-03-17 Kaushiki Mukherjee , Biswajit Paul , Sumana Karmakar

We introduce the discording power of a unitary transformation, which assesses its capability to produce quantum discord, and analyze in detail the generation of discord by relevant classes of two-qubit gates. Our measure is based on the…

Quantum Physics · Physics 2013-01-09 F. Galve , F. Plastina , M. G. A. Paris , R. Zambrini

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

We present a scheme of quantum information transmission, which transmits the quantum information contained in a single qubit via the quantum correlation shared by two parties (a two-qubit channel), whose quantum discord is non-zero. We…

Quantum Physics · Physics 2012-02-22 Lei Wang , Jie-Hui Huang , Jonathan P. Dowling , Shi-Yao Zhu

We devise and experimentally realize a procedure capable of detecting and distinguishing quantum discord and classical correlations as well the presence of factorized states in a joint system-environment setting. Our scheme builds on recent…

Quantum Physics · Physics 2014-11-14 Simone Cialdi , Andrea Smirne , Matteo G. A. Paris , Stefano Olivares , Bassano Vacchini

In contrast with entanglement, as measured by concurrence, in general, quantum discord does not possess the property of monogamy, that is, there is no tradeoff between the quantum discord shared by a pair of subsystems and the quantum…

Quantum Physics · Physics 2011-11-14 Gian Luca Giorgi

Two-qubit X-state is a large class of quantum states which plays an important role in the quantification and dynamical study of quantum correlations. However, the corresponding quantification of quantum discord is still missing for bona…

Quantum Physics · Physics 2021-06-23 Chunhe Xiong , Guijun Zhang

One-way quantum deficit and quantum discord are two important measures of quantum correlations. We revisit the relationship between them in two-qubit systems. We investigate the conditions that both one-way quantum deficit and quantum…

Quantum Physics · Physics 2016-01-12 Biao-Liang Ye , Shao-Ming Fei

Classical correlation and quantum discord are computed for two-qubit $X$-states. Our approach, which is inspired by the methods of classical polarization optics, is geometric in the sense that the entire analysis is tied to the correlation…

Quantum Physics · Physics 2013-11-04 Krishna Kumar Sabapathy , R. Simon

The non-Markovian master equations are derived to study quantum discord dynamics of two qubits coupled to a common reservoir and two independent reservoirs, respectively. We compare the dynamics under different parameters, such as reservoir…

Quantum Physics · Physics 2011-05-26 Z. -K. Su , S. -J. Jiang

We examine the possibilities of non-trivial phenomena of time-invariant entanglement and freezing dynamics of entanglement for qutrit-qutrit quantum systems. We find no evidence for time-invariant entanglement, however, we do observe that…

Quantum Physics · Physics 2019-02-28 Mazhar Ali

We study nonclassical correlations in propagating two-mode squeezed microwave states in the presence of noise. We focus on two different types of correlations, namely, quantum entanglement and quantum discord. Quantum discord has various…

The original quantum discord (QD) is shown to be not monogamous except for the three-qubit states. Recently, a complete monogamy relation for multiparty quantum system was established for entanglement in [Phys. Rev. A. {101},…

Quantum Physics · Physics 2021-10-11 Yu Guo , Lizhong Huang , Yang Zhang

We propose the information-theoretic quantity of geometric quantum discord (GQD) as an indicator of the factorization properties of a given quantum system. In particular, we show how non-vanishing discord implies that the corresponding…

High Energy Physics - Theory · Physics 2023-08-22 Souvik Banerjee , Pablo Basteiro , Rathindra Nath Das , Moritz Dorband

This paper examines the coherence in multipartite systems. We first discuss the distribution of total coherence in a given multipartite quantum state into discord between subsystems and coherent dissonance in each individual subsystem,…

Quantum Physics · Physics 2018-09-26 Zhengjun Xi