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Related papers: State Ensembles and Quantum Entropy

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We construct and explore a family of states for quantum systems in contact with two or more heath reservoirs. The reservoirs are described by equilibrium distributions. The interaction of each reservoir with the bulk of the system is…

Statistical Mechanics · Physics 2022-05-03 Mihail Mintchev

Quantum entanglement of pure states is usually quantified via the entanglement entropy, the von Neumann entropy of the reduced state. Entanglement entropy is closely related to entanglement distillation, a process for converting quantum…

Quantum Physics · Physics 2021-10-06 Tulja Varun Kondra , Chandan Datta , Alexander Streltsov

In quantum information theory, communication capacities are mostly given in terms of entropic formulas. Continuity of such entropic quantities are significant, as they ensure uniformity of measures against perturbations of quantum states.…

Quantum Physics · Physics 2023-10-19 Komal Kumar , Nirman Ganguly

The von Neumann entropy is a key quantity in quantum information theory and, roughly speaking, quantifies the amount of quantum information contained in a state when many identical and independent i.i.d. copies of the state are available,…

Quantum Physics · Physics 2019-06-05 P. Boes , J. Eisert , R. Gallego , M. P. Mueller , H. Wilming

Projective measurement can increase the entropy of a state $\rho$, the increased entropy is not only up to the basis of projective measurement, but also has something to do with the properties of the state itself. In this paper we define…

Quantum Physics · Physics 2016-10-03 Xing Chen

Environmental interactions are ubiquitous in any real-world application of a quantum information processing protocol. Such interactions result in depletion of quantum resources. Two important figure of merits in the context of quantum…

Quantum Physics · Physics 2024-06-06 Tapaswini Patro , Kaushiki Mukherjee , Nirman Ganguly

We present first measure of quantum correlation of an ensemble of multiparty states. It is based on the idea of minimal entropy production in a locally distinguishable basis measurement. It is shown to be a relative entropy distance from a…

Quantum Physics · Physics 2009-10-29 Michal Horodecki , Aditi Sen De , Ujjwal Sen

After a brief introduction to the concept of entanglement in quantum systems, I apply these ideas to many-body systems and show that the von Neumann entropy is an effective way of characterising the entanglement between the degrees of…

Statistical Mechanics · Physics 2009-11-13 John Cardy

We investigate multipartite entanglement in relation to the theoretical process of quantum state exchange. In particular, we consider such entanglement for a certain pure state involving two groups of N trapped atoms. The state, which can…

Quantum Physics · Physics 2009-11-07 D. T. Pope , G. J. Milburn

Quantum entanglement is the quantum information processing resource. Thus it is of importance to understand how much of entanglement particular quantum states have, and what kinds of laws entanglement and also transformation between…

Quantum Physics · Physics 2007-05-23 Toshiyuki Shimono

We consider the problem of determining the mixed quantum state of a large but finite number of identically prepared quantum systems from data obtained in a sequence of ideal (von Neumann) measurements, each performed on an individual copy…

Quantum Physics · Physics 2009-11-10 Franz Embacher , Heide Narnhofer

We present a detailed account of quantum state estimation by joint maximization of the likelihood and the entropy. After establishing the algorithms for both perfect and imperfect measurements, we apply the procedure to data from simulated…

We construct a complete set of Wannier functions which are localized at both given positions and momenta. This allows us to introduce the quantum phase space, onto which a quantum pure state can be mapped unitarily. Using its probability…

Statistical Mechanics · Physics 2015-06-10 Xizhi Han , Biao Wu

Transfer entropy provides a general tool for analyzing the magnitudes and directions---but not the \emph{kinds}---of information transfer in a system. We extend transfer entropy in two complementary ways. First, we distinguish…

Data Analysis, Statistics and Probability · Physics 2011-02-09 Paul L. Williams , Randall D. Beer

Experimental determination of an unknown quantum state usually requires several incompatible measurements. However, it is also possible to determine the full quantum state from a single, repeated measurement. For this purpose, the quantum…

Quantum Physics · Physics 2008-03-25 Xinhua Peng , Jiangfeng Du , Dieter Suter

This work is an application of game theory to quantum information. In a state estimate, we are given observations distributed according to an unknown distribution $P_{\theta}$ (associated with award $Q$), which Nature chooses at random from…

Quantum Physics · Physics 2011-11-10 Xianhua Dai , V. P. Belavkin

Generalizing the notion of relative entropy, the difference between a priori and a posteriori relative entropy for quantum systems is drawn. The former, known as quantum relative entropy, is associated with quantum states recognition. The…

Quantum Physics · Physics 2007-05-23 Roman R. Zapatrin

We introduce a new notion of entropy for quantum states, called contextual entropy, and show how it unifies Shannon and von Neumann entropy. The main result is that from the knowledge of the contextual entropy of a quantum state of a…

Quantum Physics · Physics 2012-08-13 Carmen Maria Constantin , Andreas Doering

In quantum information geometry, the curvature of von-Neumann entropy and relative entropy induce a natural metric on the space of mixed quantum states. Here we use this information metric to construct a random matrix ensemble for states…

Quantum Physics · Physics 2026-01-26 Harry J. D. Miller

We define a quantum entropy conditioned on post-selection which has the von Neumann entropy of pure states as a special case. This conditional entropy can take negative values which is consistent with part of a quantum system containing…

Quantum Physics · Physics 2014-09-05 Sina Salek , Roman Schubert , Karoline Wiesner