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Related papers: Chain rules for quantum channels

200 papers

We develop an approximation approach to infinite dimensional quantum channels based on detailed investigation of the continuity properties of entropic characteristics of quantum channels and operations (trace-nonincreasing completely…

Quantum Physics · Physics 2008-12-17 M. E. Shirokov , A. S. Holevo

We connect two key concepts in quantum information: compatibility and divisibility of quantum channels. Two channels are compatible if they can be both obtained via marginalization from a third channel. A channel divides another channel if…

Quantum Physics · Physics 2022-07-27 Cristhiano Duarte , Lorenzo Catani , Raphael C. Drumond

Quantum networks offer a realistic and practical scheme for generating multiparticle entanglement and implementing multiparticle quantum communication protocols. However, the correlations that can be generated in networks with quantum…

Quantum Physics · Physics 2023-08-29 Kiara Hansenne , Otfried Gühne

Transmitting data reliably over noisy communication channels is one of the most important applications of information theory, and well understood when the channel is accurately modelled by classical physics. However, when quantum effects…

We analyze two ways to obtain distinguishability measures between quantum maps by employing the square root of the quantum Jensen-Shannon divergence, which forms a true distance in the space of density operators. The arising measures are…

Quantum Physics · Physics 2023-07-19 Diego G. Bussandri , Pedro W. Lamberti , Karol Życzkowski

We investigate an original family of quantum distinguishability problems, where the goal is to perfectly distinguish between $M$ quantum states that become identical under a completely decohering map. Similarly, we study distinguishability…

Quantum Physics · Physics 2019-11-06 Kamil Korzekwa , Stanisław Czachórski , Zbigniew Puchała , Karol Życzkowski

The action of a channel on a quantum system, when non trivial, always causes deterioration of initial quantum resources, understood as the entanglement initially shared by the input system with some reference purifying it. One effective way…

Quantum Physics · Physics 2008-11-06 Francesco Buscemi

We study the problem of quantum channel discrimination between two channels with an adversary input party (a.k.a. a jammer). This setup interpolates between the best-case channel discrimination as studied by (Wang & Wilde, 2019) and the…

Quantum Physics · Physics 2025-10-10 Kun Fang , Michael X. Cao

Quantum channel estimation and discrimination are fundamentally related information processing tasks of interest in quantum information science. In this paper, we analyze these tasks by employing the right logarithmic derivative Fisher…

Quantum Physics · Physics 2021-03-02 Vishal Katariya , Mark M. Wilde

This paper considers the comparison of noisy channels from the viewpoint of statistical decision theory. Various orderings are discussed, all formalizing the idea that one channel is "better" than another for information transmission. The…

Information Theory · Computer Science 2018-03-09 Francesco Buscemi

Quantum coherence is a fundamental aspect of quantum physics and plays a central role in quantum information science. This essential property of the quantum states could be fragile under the influence of the quantum operations. The extent…

Quantum Physics · Physics 2018-10-18 Fereshte Shahbeigi , Seyed Javad Akhtarshenas

Identifying the precise moment when a quantum channel undergoes a change is a fundamental problem in quantum information theory. We study how accurately one can determine the time at which a channel transitions to another. We investigate…

Quantum Physics · Physics 2026-04-15 Kenji Nakahira

Unambiguous unitary maps and unambiguous unitary quantum channels are introduced and some of their properties are derived. These properties ensure certain simple form for the measurements involved in realizing an unambiguous unitary quantum…

Quantum Physics · Physics 2008-11-14 Shengjun Wu , Xuemei Chen

One of the fundamental tasks in quantum information processing is to measure the quantum channels. Similar to measurements of quantum states, measurements of quantum channels are inherently stochastic, that is, quantum theory provides a…

Quantum Physics · Physics 2024-06-24 Taihei Kimoto , Takayuki Miyadera

The data processing inequality is the most basic requirement for any meaningful measure of information. It essentially states that distinguishability measures between states decrease if we apply a quantum channel and is the centerpiece of…

Quantum Physics · Physics 2022-11-30 Christoph Hirche , Cambyse Rouzé , Daniel Stilck França

A set of classical or quantum states is equivalent to another one if there exists a pair of classical or quantum channels mapping either set to the other one. For dichotomies (pairs of states), this is closely connected to (classical or…

Quantum Physics · Physics 2024-07-09 Niklas Galke , Lauritz van Luijk , Henrik Wilming

In the problem of binary quantum channel discrimination with product inputs, the supremum of all type II error exponents for which the optimal type I errors go to zero is equal to the Umegaki channel relative entropy, while the infimum of…

Quantum Physics · Physics 2025-08-12 Milán Mosonyi , Fumio Hiai

Entanglement is a key issue in the quantum physics which gives rise to resources for achieving tasks that are not possible within the realm of classical physics. Quantum entanglement varies with the evolution of the quantum systems. It is…

Quantum Physics · Physics 2019-06-06 Long-Mei , Yang Tao Li , Shao-Ming Fei , Zhi-Xi Wang

We investigate quantum R\'enyi entropic quantities, specifically those derived from 'sandwiched' divergence. This divergence is one of several proposed R\'enyi generalisations of the quantum relative entropy. We may define R\'enyi…

Quantum Physics · Physics 2021-10-04 Alexander McKinlay

Based on the resource theory for quantifying the coherence of quantum channels, we introduce a new coherence quantifier for quantum channels via maximum relative entropy. We prove that the maximum relative entropy for coherence of quantum…