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Related papers: Extremality conditions for generalized channels

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Measurements on quantum channels are described by so-called process operator valued measures, or process POVMs. We study implementing schemes of extremal process POVMs. As it turns out, the corresponding measurement must satisfy certain…

Quantum Physics · Physics 2015-12-30 Anna Jencova

We propose a categorical foundation for the connection between pure and mixed states in quantum information and quantum computation. The foundation is based on distributive monoidal categories. First, we prove that the category of all…

Logic in Computer Science · Computer Science 2019-04-25 Mathieu Huot , Sam Staton

This paper reviews generalized Pareto copulas (GPC), which turn out to be a key to multivariate extreme value theory. Any GPC can be represented in an easy analytic way using a particular type of norm on $\mathbb{R}^d$, called $D$-norm. The…

Statistics Theory · Mathematics 2018-11-26 Michael Falk , Simone Padoan , Florian Wisheckel

Quantum channel, as the information transmitter, is an indispensable tool in quantum information theory. In this paper, we study a class of special quantum channels named the mixed-permutation channels. The properties of these channels are…

Quantum Physics · Physics 2024-01-15 Lin Zhang , Ming-Jing Zhao

The expected indefinite causal structure in quantum gravity poses a challenge to the notion of entanglement: If two parties are in an indefinite causal relation of being spacelike and timelike, can they still be entangled? If so, how does…

Quantum Physics · Physics 2018-02-27 Ding Jia

We give a complete characterization for pure quantum measurements, i.e., for POVMs which are extremals in the convex set of all POVMs. Such measurements are free from classical noise. The characterization is valid both in discrete and…

Quantum Physics · Physics 2011-02-18 Juha-Pekka Pellonpää

Quantum masking is a special type of secret sharing in which some information gets reversibly distributed into a multipartite system, leaving the original information inaccessible to each subsystem. This paper proposes a dynamical extension…

Quantum Physics · Physics 2026-05-07 Anna Honeycutt , Hailey Murray , Eric Chitambar

A new notation for the quantum teleportation of finite dimensional quantum state through a generally entangled quantum channel is introduced. For a given quantum channel an explict mathematical criterion that governs the faithful…

Quantum Physics · Physics 2009-11-07 Chong Li , He-Shan Song , Yao-Xing Luo

In the problem of channel resolvability, where a given output probability distribution via a channel is approximated by transforming the uniform random numbers, characterizing the asymptotically minimum rate of the size of the random…

Information Theory · Computer Science 2017-01-31 Hideki Yagi

A generalized teleportation protocol (GTP) for N qubits is presented, where the teleportation channels are non-maximally entangled and all the free parameters of the protocol are considered: Alice's measurement basis, her sets of acceptable…

Quantum Physics · Physics 2009-11-11 Goren Gordon , Gustavo Rigolin

The most important ability of a quantum channel is to preserve the quantum properties of transmitted quantum states. We experimentally demonstrate a continuous-variable system for efficient benchmarking of quantum channels. We probe the…

Generalized quantum measurements with N distinct outcomes are used for determining the density matrix, of order d, of an ensemble of quantum systems. The resulting probabilities are represented by a point in an N-dimensional space. It is…

Quantum Physics · Physics 2009-10-31 Asher Peres , Daniel Terno

Quantum channels can represent dynamic resources, which are indispensable elements in many physical scenarios. To describe certain facets of nonclassicality of the channels, it is necessary to quantify their properties. In the framework of…

Quantum Physics · Physics 2022-11-23 Huaqi Zhou , Ting Gao , Fengli Yan

Although many quantum channels satisfy Completely Positive Trace Preserving (CPTP) condition, there are valid quantum channels that can be non-completely positive (NCP). As memory effects can provide advantages in the dynamics of noisy…

Quantum Physics · Physics 2026-02-18 Anumita Mukhopadhyay , Praggnyamita Ghosh , Shibdas Roy

The L\"uders rule provides a way to define a quantum channel given a quantum measurement. Using this construction, we establish an if-and-only-if condition for the existence of a $d$-dimensional Symmetric Informationally Complete quantum…

Quantum Physics · Physics 2020-02-07 John B. DeBrota , Blake C. Stacey

Using well known duality between quantum maps and states of composite systems we introduce the notion of Schmidt number of a quantum channel. It enables one to define classes of quantum channels which partially break quantum entanglement.…

Quantum Physics · Physics 2007-05-23 Dariusz Chruscinski , Andrzej Kossakowski

Quantum mechanics has greatly impacted our understanding of the microscopic nature. One of the key concepts of this theory is generalized measurements, which have proven useful in various quantum information processing tasks. However,…

Quantum Physics · Physics 2025-10-07 Piotr Mironowicz , Marcus Grünfeld , Mohamed Bourennane

As our main result we show that, in order to achieve the randomness assisted message - and entanglement transmission capacities of a finite arbitrarily varying quantum channel it is not necessary that sender and receiver share…

Quantum Physics · Physics 2015-06-12 Holger Boche , Janis Noetzel

A bipartite quantum channel represents the interaction between systems, generally allowing for exchange of information. A special class of bipartite channels are the no-signaling ones, which do not allow communication. In Ref. [1] it has…

Quantum Physics · Physics 2011-01-28 Giacomo Mauro D'Ariano , Stefano Facchini , Paolo Perinotti

We study one-mode Gaussian quantum channels in continuous-variable systems by performing a black-box characterization using complete positivity and trace preserving conditions, and report the existence of two subsets that do not have a…

Quantum Physics · Physics 2020-10-23 David Davalos , Camilo Moreno , Juan-Diego Urbina , Carlos Pineda