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Related papers: Capacity Bounds via Operator Space Methods

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We establish the classical capacity of optical quantum channels as a sharp transition between two regimes---one which is an error-free regime for communication rates below the capacity, and the other in which the probability of correctly…

Quantum Physics · Physics 2015-03-17 Bhaskar Roy Bardhan , Raul Garcia-Patron , Mark M. Wilde , Andreas Winter

The study of free-space quantum communications requires tools from quantum information theory, optics and turbulence theory. Here we combine these tools to bound the ultimate rates for key and entanglement distribution through a free-space…

Quantum Physics · Physics 2021-05-10 Stefano Pirandola

Quantum channels are known to provide qualitatively better information transfer capacities over their classical counterparts. Examples include quantum cryptography, quantum dense coding, and quantum teleportation. This is a short review on…

Quantum Physics · Physics 2015-03-19 Aditi Sen De , Ujjwal Sen

We define here a new kind of quantum channel capacity by extending the concept of zero-error capacity for a noisy quantum channel. The necessary requirement for which a quantum channel has zero-error capacity greater than zero is given.…

Quantum Physics · Physics 2007-05-23 Rex A. C. Medeiros , Francisco M. De Assis

We present a communication protocol for the erasure channel assisted by backward classical communication, which achieves a significantly better rate than the best prior result. In addition, we prove an upper bound for the capacity of the…

Quantum Physics · Physics 2013-05-29 Debbie Leung , Joungkeun Lim , Peter Shor

This paper investigates properties of noisy quantum information channels. We define a new quantity called {\em coherent information} which measures the amount of quantum information conveyed in the noisy channel. This quantity can never be…

Quantum Physics · Physics 2009-10-30 Benjamin Schumacher , M. A. Nielsen

In this work we prove that the possibility of superactivation of quantum channel capacities is determined by the mathematical properties of the quantum relative entropy function. Before our work this fundamental and purely mathematical…

Quantum Physics · Physics 2012-06-26 Laszlo Gyongyosi , Sandor Imre

We give a short proof that the coherent information is an achievable rate for the transmission of quantum information through a noisy quantum channel. Our method is to produce random codes by performing a unitarily covariant projective…

Quantum Physics · Physics 2016-11-17 Patrick Hayden , Michal Horodecki , Andreas Winter , Jon Yard

We study the capacity of a quantum channel for retrocausal communication, where messages are transmitted backward in time, from a sender in the future to a receiver in the past, through a noisy postselected closed timelike curve (P-CTC)…

Quantum Physics · Physics 2026-04-17 Kaiyuan Ji , Seth Lloyd , Mark M. Wilde

We derive bounds on the noncoherent capacity of a very general class of multiple-input multiple-output channels that allow for selectivity in time and frequency as well as for spatial correlation. The bounds apply to peak-constrained…

Information Theory · Computer Science 2008-01-29 Ulrich G. Schuster , Giuseppe Durisi , Helmut Bölcskei , H. Vincent Poor

The capacity of a channel can usually be characterized as a maximization of certain entropic quantities. From a practical point of view it is of primary interest to not only compute the capacity value, but also to find the corresponding…

Information Theory · Computer Science 2023-05-25 Holger Boche , Rafael F. Schaefer , H. Vincent Poor

A key open question in quantum computation is what advantages quantum neural networks (QNNs) may have over classical neural networks (NNs), and in what situations these advantages may transpire. Here we address this question by studying the…

Quantum Physics · Physics 2019-08-06 Logan G. Wright , Peter L. McMahon

The task of determining whether a given quantum channel has positive capacity to transmit quantum information is a fundamental open problem in quantum information theory. In general, the coherent information needs to be computed for an…

Quantum Physics · Physics 2022-08-17 Satvik Singh , Nilanjana Datta

In this work we design a specific simulation tool for quantum channels which is based on the use of a control system. This allows us to simulate an average quantum channel which is expressed in terms of an ensemble of channels, even when…

Quantum Physics · Physics 2018-12-19 Stefano Pirandola , Riccardo Laurenza , Leonardo Banchi

We consider quantum channels with one sender and two receivers, used in several different ways for the simultaneous transmission of independent messages. We begin by extending the technique of superposition coding to quantum channels with a…

Quantum Physics · Physics 2011-10-25 Jon Yard , Patrick Hayden , Igor Devetak

Most communication channels are subjected to noise. One of the goals of Information Theory is to add redundancy in the transmission of information so that the information is transmitted reliably and the amount of information transmitted…

Information Theory · Computer Science 2018-03-21 David Elkouss , David Pérez-García

We construct a class of quantum channels in arbitrary dimensions for which entanglement improves the performance of the channel. The channels have correlated noise and when the level of correlation passes a critical value we see a sharp…

Quantum Physics · Physics 2009-11-13 V. Karimipour , L. Memarzadeh

Information theory establishes the ultimate limits on performance for noisy communication systems [Shannon48]. An accurate model of a physical communication device must include quantum effects, but typically including these makes the theory…

Quantum Physics · Physics 2013-12-20 Graeme Smith , John A. Smolin

This paper investigates the capacity region of the optical intensity broadcast channels (OI-BCs), where the input is subject to a peak-intensity constraint, an average-intensity constraint, or both. By leveraging the decomposition results…

Information Theory · Computer Science 2023-03-02 Sufang Yang , Longguang Li , Jintao Wang

The design of error-correcting codes used in modern communications relies on information theory to quantify the capacity of a noisy channel to send information [1]. This capacity can be expressed using the mutual information between input…

Quantum Physics · Physics 2019-07-17 M. B. Hastings
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