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Related papers: A Condition for the Nullity of Quantum Discord

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We introduce a composition of quantum states of a bipartite system which is based on the reshuffling of density matrices. This non-Abelian product is associative and stems from the composition of quantum maps acting on a simple quantum…

Quantum Physics · Physics 2009-11-13 Wojciech Roga , Mark Fannes , Karol Zyczkowski

Quantum correlation often refers to correlations exhibited by two or more local subsystems under a suitable measurement. These correlations are beyond the framework of classical statistics and the associated classical probability…

Quantum Physics · Physics 2022-11-09 Biveen Shajilal , Elanor Huntington , Ping Koy Lam , Syed Assad

We prove a theorem for coding mixed-state quantum signals. For a class of coding schemes, the von Neumann entropy $S$ of the density operator describing an ensemble of mixed quantum signal states is shown to be equal to the number of…

Quantum Physics · Physics 2015-06-26 Hoi-Kwong Lo

It is observed that the entropy reduction (the information gain in the initial terminology) of an efficient (ideal or pure) quantum measurement coincides with the generalized quantum mutual information of a q-c channel mapping an a priori…

Quantum Physics · Physics 2015-05-20 M. E. Shirokov

In this brief review, we discuss the role that quantum correlations, as quantified by quantum discord, play in two interesting settings. The first one is discerning which unitaries have been applied on a quantum system, by taking advantage…

Quantum Physics · Physics 2017-08-01 Mile Gu , Stefano Pirandola

We discuss the notion of hidden correlations in classical and quantum indivisible systems along with such characteristics of the correlations as the mutual information and conditional information corresponding to the entropic subadditivity…

Quantum Physics · Physics 2017-12-22 Margarita A. Man'ko , Vladimir I. Man'ko

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

Entanglement does not describe all quantum correlations and several authors have shown the need to go beyond entanglement when dealing with mixed states. Various different measures have sprung up in the literature, for a variety of reasons,…

Quantum Physics · Physics 2023-01-23 Aharon Brodutch , Kavan Modi

We investigate whether the presence or absence of correlations between subsystems of an N-partite quantum system is solely constrained by the non-negativity and monotonicity of mutual information. We argue that this relatively simple…

Quantum states can be subjected to classical measurements, whose incompatibility, or uncertainty, can be quantified by a comparison of certain entropies. There is a long history of such entropy inequalities between position and momentum.…

Quantum Physics · Physics 2015-06-04 Rupert L. Frank , Elliott H. Lieb

New quantum entropic inequality for states of system of n >_ 1 qudits is obtained. The inequality has the form of quantum subadditivity condition of bipartite qudit system and coincides with this subadditivity condition for the system of…

Quantum Physics · Physics 2019-02-12 V. N. Chernega , O. V. Man'ko , V. I. Man'ko

Superlocality and superunsteerability provide operational characterization of quantum correlations in certain local and unsteerable states respectively. Such quantum correlated states have a nonzero quantum discord. A two-way nonzero…

Quantum Physics · Physics 2023-10-19 Chellasamy Jebarathinam , Debarshi Das , R. Srikanth

Quantum coherence as an important quantum resource plays a key role in quantum theory. In this paper, using entropy-based measures, we investigate the relations between quantum correlated coherence, which is the coherence between subsystems…

Quantum Physics · Physics 2017-03-03 Xiao-Li Wang , Qiu-Ling Yue , Chao-Hua Yu , Fei Gao , Su-Juan Qin

It is well known that the von Neumann entropy is continuous on a subset of quantum states with bounded energy provided the Hamiltonian $H$ of the system satisfies the condition $\Tr\exp(-cH)<+\infty$ for any $c>0$. In this note we consider…

Quantum Physics · Physics 2012-01-06 M. E. Shirokov

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

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

We find the necessary and sufficient conditions for the entropy rate of the system to be zero under any system-environment Hamiltonian interaction. We call the class of system-environment states that satisfy this condition lazy states. They…

Quantum Physics · Physics 2011-02-09 Cesar A. Rodriguez-Rosario , Gen Kimura , Hideki Imai , Alan Aspuru-Guzik

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

Quantum discord, a kind of quantum correlation, is defined as the difference between quantum mutual information and classical correlation in a bipartite system. It has been discussed so far for small systems with only a few independent…

Quantum Physics · Physics 2012-04-26 sai vinjanampathy , A. R. P. Rau

We discuss a generalization of the conditional entropy and one-way information deficit in quantum systems, based on general entropic forms. The formalism allows to consider simple entropic forms for which a closed evaluation of the…

Quantum Physics · Physics 2017-12-29 N. Canosa , M. Cerezo , N. Gigena , R. Rossignoli