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Related papers: Geometric Discord for Multi-qubit Systems

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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

The formation of multipartite quantum entanglement by repeated operation of one and two qubit gates is examined. The resulting entanglement is evaluated using two measures: the average bipartite entanglement and the Groverian measure. A…

Quantum Physics · Physics 2009-11-13 Yonatan Most , Yishai Shimoni , Ofer Biham

Preserving quantum coherence is fundamental challenge in the field of quantum computation. Here, I investigate the frozen discord phenomenon and non-Markovianity for qubits experiencing local dephasing in a classical environment. The…

Quantum Physics · Physics 2020-11-10 Bin Yi

We solve the quantum discord completely as an optimization of certain one variable function for arbitrary two qubit X state. Exact solutions of the quantum discord are obtained for several nontrivial regions of the five parametric space for…

Quantum Physics · Physics 2016-08-31 Naihuan Jing , Bing Yu

We describe a resource-efficient approach to studying many-body quantum states on noisy, intermediate-scale quantum devices. We employ a sequential generation model that allows us to bound the range of correlations in the resulting…

Quantum Physics · Physics 2021-03-05 Johannes Borregaard , Matthias Christandl , Daniel Stilck França

We investigated the dissipative dynamics of quantum discord for correlated qubits under Markovian environments. The basic idea in the present scheme is that quantum discord is more general, and possibly more robust and fundamental, than…

Quantum Physics · Physics 2015-06-04 M. Mahdian , R. Yousefjani , S. Salimi

Quantum correlations between parts of a composite system most clearly reveal themselves through entanglement. Designing, maintaining, and controlling entangled systems is very demanding, which raises the stakes for understanding the…

Quantum Physics · Physics 2019-09-04 Matthew A. Hunt , Igor V. Lerner , Igor V. Yurkevich , Yuval Gefen

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

Except for a few special states, computing quantum discord remains a complicated optimization process. In this paper we present analytical solutions for computing quantum discord of the most general class of X-states and the criteria for…

Quantum Physics · Physics 2016-08-31 A. Maldonado-Trapp , Anzi Hu , Luis Roa

We introduce a measure of quantum correlations in the $N$-qubit quantum system which is invariant with respect to the $SU(2^N)$ group of transformations of this system. This measure is a modification of the quantum discord introduced…

Quantum Physics · Physics 2011-10-18 A. I. Zenchuk

In recent years the paradigm based on entanglement as the unique measure of quantum correlations has been challenged by the rise of new correlation concepts, such as quantum discord, able to reveal quantum correlations that are present in…

Quantum Physics · Physics 2013-05-30 Paolo Giorda , Michele Allegra , Matteo G. A. Paris

It has recently been pointed out that the geometric quantum discord, as defined by the Hilbert-Schmidt norm (2-norm), is not a good measure of quantum correlations, since it may increase under local reversible operations on the unmeasured…

Quantum Physics · Physics 2013-06-11 F. M. Paula , Thiago. R. de Oliveira , M. S. Sarandy

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

The ability to perform gates in multiqubit systems that are robust to noise is of crucial importance for the advancement of quantum information technologies. However, finding control pulses that cancel noise while performing a gate is made…

Quantum Physics · Physics 2021-03-17 Donovan Buterakos , Sankar Das Sarma , Edwin Barnes

Motivated by recent numerous works on the interplay among various measures of quantum correlations, we aim to investigate the relationship between the violation of Clauser-Horne-Shimony-Holt (CHSH) Bell inequality and geometric measure of…

Quantum Physics · Physics 2013-03-21 Y. Yao , H. W. Li , M. Li , Z. Q. Yin , W. Chen , Z. F. Han

We study the relative strength of classical and quantum correlations, as measured by discord, for two-qubit states. Quantum correlations appear only in the presence of classical correlations, while the reverse is not always true. We…

Quantum Physics · Physics 2011-01-17 Fernando Galve , Gian Luca Giorgi , Roberta Zambrini

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

The interaction between solid-state qubits and their environmental degrees of freedom produces non-unitary effects like decoherence and dissipation. Uncontrolled decoherence is one of the main obstacles that must be overcome in quantum…

Quantum Physics · Physics 2014-11-24 Paula I. Villar , Fernando C. Lombardo

Few studies explored the dynamics of non-classical correlations besides entanglement in open multipartite quantum systems. Here, we address the time-evolution of quantum discord and entanglement in a model of three non-interacting qubits…

Quantum Physics · Physics 2013-04-11 Fabrizio Buscemi , Paolo Bordone

Quantum discord is an effective measure of quantum correlation introduced by Olliver and Zurek. We evaluate analytically the quantum discord for a large family of non-X-states. Exact solutions of the quantum discord are obtained of the four…

Quantum Physics · Physics 2020-04-27 Jianming Zhou , Xiaoli Hu , Naihuan Jing