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Related papers: Achieving the Holevo bound via sequential measurem…

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The amount of information that can be accessed via measurement of a quantum system prepared in different states is limited by the Kholevo bound. We present a simple proof of this theorem and its extension to sequential measurements based on…

Quantum Physics · Physics 2007-05-23 N. J. Cerf , C. Adami

Dense coding with non-maximally entangled states has been investigated in many different scenarios. We revisit this problem for protocols adopting the standard encoding scheme. In this case, the set of possible classical messages cannot be…

Quantum Physics · Physics 2017-03-03 Roger Alfredo Kögler , Leonardo Neves

This paper considers the problem of efficiently transmitting quantum states through a network. It has been known for some time that without additional assumptions it is impossible to achieve this task perfectly in general -- indeed, it is…

Quantum Physics · Physics 2016-05-30 Hirotada Kobayashi , François Le Gall , Harumichi Nishimura , Martin Roetteler

We give the trade-off curve showing the capacity of a quantum channel as a function of the amount of entanglement used by the sender and receiver for transmitting information. The endpoints of this curve are given by the…

Quantum Physics · Physics 2007-05-23 Peter W. Shor

We consider the problem of slotted asynchronous coded communication, where in each time frame (slot), the transmitter is either silent or transmits a codeword from a given (randomly selected) codebook. The task of the decoder is to decide…

Information Theory · Computer Science 2013-08-22 Neri Merhav

Quantum error correcting (QEC) codes protect quantum information from decoherence, as long as error rates fall below critical error thresholds. In general, obtaining thresholds implies simulating the QEC procedure using, in general,…

Quantum Physics · Physics 2024-10-17 Luis Colmenarez , Ze-Min Huang , Sebastian Diehl , Markus Müller

An additive noise channel is considered, in which the distribution of the noise is nonparametric and unknown. The problem of learning encoders and decoders based on noise samples is considered. For uncoded communication systems, the problem…

Information Theory · Computer Science 2021-11-17 Nir Weinberger

When classical or quantum information is broadcast to separate receivers, there exist codes that encrypt the encoded data such that the receivers cannot recover it when performing local operations and classical communication, but they can…

Quantum Physics · Physics 2016-05-31 Cosmo Lupo , Mark M. Wilde , Seth Lloyd

We extend a low-rate improvement of the random coding bound on the reliability of a classical discrete memoryless channel to its quantum counterpart. The key observation that we make is that the problem of bounding below the error exponent…

Quantum Physics · Physics 2007-05-23 Alexander Barg

We investigate the quantitative relationship between operator spreading and classical information propagation in quantum systems. Focusing on a bi-partite quantum channel, we derive new upper and lower bounds on the Holevo capacity, a…

Quantum Physics · Physics 2025-05-14 Cheng Shang , Zhi-Guang Lu , Hayato Kinkawa , Tomotaka Kuwahara

Using random Gaussian vectors and an information-uncertainty relation, we give a proof that the coherent information is an achievable rate for entanglement transmission through a noisy quantum channel. The codes are random subspaces…

Quantum Physics · Physics 2012-07-06 Patrick Hayden , Peter W. Shor , Andreas Winter

Classical communications are used in the post-processing procedure of quantum key distribution. Since the security of quantum key distribution is based on the principles of quantum mechanics, intuitively the secret key can only be derived…

Quantum Physics · Physics 2008-05-05 Yong-gang Tan , Qing-yu Cai

Heralding techniques are useful in quantum communication to circumvent losses without resorting to error correction schemes or quantum repeaters. Such techniques are realized, for example, by monitoring for photon loss at the receiving end…

We study the reliability function of general classical-quantum channels, which describes the optimal exponent of the decay of decoding error when the communication rate is below the capacity. As the main result, we prove a lower bound, in…

Quantum Physics · Physics 2025-02-18 Ke Li , Dong Yang

In this work, we study the transmission of classical information through three completely depolarizing channels in superposition of different causal orders. We thus introduce the quantum 3-switch as a resource for quantum communications. We…

We consider asynchronous communication over point-to-point discrete memoryless channels. The transmitter starts sending one block codeword at an instant that is uniformly distributed within a certain time period, which represents the level…

Information Theory · Computer Science 2007-08-01 Aslan Tchamkerten , Venkat Chandar , Gregory Wornell

We experimentally demonstrate the achievement of the entanglement assisted capacity for classical information transmission over a depolarizing channel. The implementation is based on the generation and local manipulation of 2-qubit Bell…

Quantum Physics · Physics 2015-06-05 Andrea Chiuri , Sandro Giacomini , Chiara Macchiavello , Paolo Mataloni

We derive a closed-form achievable rate for entanglement-assisted classical communication over a lossy thermal-noise bosonic channel, where the entanglement is in the form of a Two-Mode Squeezed Vacuum (TMSV) modulation restricted to Phase…

Quantum Physics · Physics 2024-10-23 Shang-Jen Su , Shi-Yuan Wang , Matthieu R. Bloch , Zheshen Zhang

Quantum error correction promises a viable path to fault-tolerant computations, enabling exponential error suppression when the device's error rates remain below the protocol's threshold. This threshold, however, strongly depends on the…

Quantum Physics · Physics 2026-05-11 Maurice D. Hanisch , Bence Hetényi , James R. Wootton

The field of quantum communications promises the faithful distribution of quantum information, quantum entanglement, and absolutely secret keys, however, the highest rates of these tasks are fundamentally limited by the transmission…

Quantum Physics · Physics 2022-11-18 Matthew S. Winnel , Joshua J. Guanzon , Nedasadat Hosseinidehaj , Timothy C. Ralph