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Related papers: Quantum Capacities of Bosonic Channels

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We present a general model for quantum channels with memory, and show that it is sufficiently general to encompass all causal automata: any quantum process in which outputs up to some time t do not depend on inputs at times t' > t can be…

Quantum Physics · Physics 2009-11-11 Dennis Kretschmann , Reinhard F. Werner

Quantum channels model many physical processes. For this reason, hypothesis testing between quantum channels is a fundamental task in quantum information theory. Here we consider the paradigmatic case of channel position finding, where the…

Quantum Physics · Physics 2021-04-28 Jason L. Pereira , Quntao Zhuang , Stefano Pirandola

Bosonic channels describe quantum-mechanically many practical communication links such as optical, microwave, and radiofrequency. We investigate the maximum rates for the bosonic multiple access channel (MAC) in the presence of thermal…

Quantum Physics · Physics 2022-07-19 Evan J. D. Anderson , Boulat A. Bash

For a quantum channel of additive Gaussian noise with loss, in the general case of $n$ copies input, we show that up to first order perturbation, any non-Gaussian perturbation to the product thermal state input has a less quantum…

Quantum Physics · Physics 2007-10-03 Xiao-yu Chen

We establish several upper bounds on the energy-constrained quantum and private capacities of all single-mode phase-insensitive bosonic Gaussian channels. The first upper bound, which we call the "data-processing bound," is the simplest and…

Quantum Physics · Physics 2018-06-18 Kunal Sharma , Mark M. Wilde , Sushovit Adhikari , Masahiro Takeoka

A model of quantum noisy channel with input encoding by a classical random vector is described. An equation of optimality is derived to determine a complete set of wave functions describing quantum decodings based on quasi-measurements…

Quantum Physics · Physics 2007-05-23 V. P. Belavkin , R. L. Stratonovich

Quantum capacity, as the key figure of merit for a given quantum channel, upper bounds the channel's ability in transmitting quantum information. Identifying different type of channels, evaluating the corresponding quantum capacity and…

Quantum Physics · Physics 2023-03-08 Changchun Zhong , Changhun Oh , Liang Jiang

Quantum information characteristics, such as quantum mutual information, loss, noise and coherent information are explicitly calculated for Bosonic attenuation/amplification channel with input Gaussian state. The coherent information is…

Quantum Physics · Physics 2007-05-23 Alexander S. Holevo

We investigate Gaussian quantum states in view of their exceptional role within the space of all continuous variables states. A general method for deriving extremality results is provided and applied to entanglement measures, secret key…

Quantum Physics · Physics 2009-11-11 Michael M. Wolf , Geza Giedke , J. Ignacio Cirac

Recently, the Gaussian optimizer conjecture in quantum information theory was confirmed for bosonic Gaussian gauge-covariant or contravariant channels. These results use the i.i.d. model of the quantum noise. In this paper we consider…

Quantum Physics · Physics 2018-12-12 A. S. Holevo

We test a general method to detect lower bounds of the quantum channel capacity for two-qubit correlated channels. We consider in particular correlated dephasing, depolarising and amplitude damping channels. We show that the method is…

Quantum Physics · Physics 2016-12-01 Chiara Macchiavello , Massimiliano F. Sacchi

The quantum capacity of a memoryless channel is often used as a single figure of merit to characterize its ability to transmit quantum information coherently. The capacity determines the maximal rate at which we can code reliably over…

Quantum Physics · Physics 2016-05-10 Marco Tomamichel , Mario Berta , Joseph M. Renes

A classification of one-mode Gaussian channels is given up to canonical unitary equivalence. A complementary to the quantum channel with additive classical Gaussian noise is described providing an example of one-mode Gaussian channel which…

Quantum Physics · Physics 2010-12-30 A. S. Holevo

Using a technique based on quantum teleportation, we simplify the most general adaptive protocols for key distribution, entanglement distillation and quantum communication over a wide class of quantum channels in arbitrary dimension. Thanks…

Quantum Physics · Physics 2018-05-16 Stefano Pirandola , Riccardo Laurenza

We consider quantum channels with two senders and one receiver. For an arbitrary such channel, we give multi-letter characterizations of two different two-dimensional capacity regions. The first region is comprised of the rates at which it…

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

We consider quantum channels with two senders and one receiver. For an arbitrary such channel, we give multi-letter characterizations of two different two-dimensional capacity regions. The first region characterizes the rates at which it is…

Information Theory · Computer Science 2011-10-25 Jon Yard , Igor Devetak , Patrick Hayden

We study information transmission over a fully correlated amplitude damping channel acting on two qubits. We derive the single-shot classical channel capacity and show that entanglement is needed to achieve the channel best performance. We…

Quantum Physics · Physics 2013-11-01 A. D'Arrigo , G. Benenti , G. Falci , C. Macchiavello

We provide a simple and realistic model to study memory effects in a lossy bosonic quantum channel over arbitrary number of uses. The noise correlation among different uses is introduced by contiguous modes interactions which results in an…

Quantum Physics · Physics 2009-11-13 O. V. Pilyavets , V. G. Zborovskii , S. Mancini

Compound channel models offer a simple and straightforward way of analyzing the stability of decoder design under model variations. With this work we provide a coding theorem for a large class of practically relevant compound channel…

Information Theory · Computer Science 2021-05-11 Andrea Cacioppo , Janis Nötzel , Matteo Rosati

Standard communication systems have transmission spectra that characterize their ability to perform frequency multiplexing over a finite bandwidth. Realistic quantum signals in quantum communication systems like transducers are inherently…

Quantum Physics · Physics 2025-02-14 Aditya Gandotra , Zhaoyou Wang , Aashish A. Clerk , Liang Jiang