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We present an algorithm for calculation of the Gaussian classical capacity of a quantum bosonic memory channel with additive Gaussian noise. The algorithm, restricted to Gaussian input states, is applicable to all channels with noise…

Quantum Physics · Physics 2015-03-17 Joachim Schäfer , Evgueni Karpov , Nicolas J. Cerf

We construct a relativistic quantum communication channel between two localized qubit systems, mediated by a relativistic quantum field, that can achieve the theoretical maximum for the quantum capacity in arbitrary curved spacetimes using…

Quantum Physics · Physics 2025-07-03 Michael Kasprzak , Erickson Tjoa

Channel capacity describes the size of the nearly ideal channels, which can be obtained from many uses of a given channel, using an optimal error correcting code. In this paper we collect and compare minor and major variations in the…

Quantum Physics · Physics 2009-11-10 Dennis Kretschmann , Reinhard F Werner

Quantum communication theory focuses on the study of quantum channels for transmitting quantum information, where the transmission rate is measured by quantum channel capacity. This quantity exhibits several intriguing properties, such as…

Quantum Physics · Physics 2025-01-14 Changchun Zhong

Passive environment assisted communication takes place via a quantum channel modeled as a unitary interaction between the information carrying system and an environment, where the latter is controlled by a passive helper, who can set its…

Quantum Physics · Physics 2021-12-28 Samad Khabbazi Oskouei , Stefano Mancini , Andreas Winter

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

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

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

In this article, we are proposing a closed-form solution for the capacity of the single quantum channel. The Gaussian distributed input has been considered for the analytical calculation of the capacity. In our previous couple of papers, we…

Information Theory · Computer Science 2023-02-17 Mouli Chakraborty , Harun Siljak , Indrakshi Dey , Nicola Marchetti

Quantum network is the key to enable distributed quantum information processing. As the single-link communication rate decays exponentially with the distance, to enable reliable end-to-end quantum communication, the number of nodes needs to…

Quantum Physics · Physics 2021-08-17 Quntao Zhuang , Bingzhi Zhang

For a partially degradable (PD) channel, the channel output state can be used to simulate the degraded environment state. The quantum capacity of a PD channel has been proven to be additive. Here, we show that the private classical capacity…

Quantum Physics · Physics 2015-06-16 Laszlo Gyongyosi

We determine the capacity of the classical compound quantum wiretapper channel with channel state information at the transmitter. Moreover we derive a lower bound on the capacity of this channel without channel state information and…

Quantum Physics · Physics 2012-02-06 Minglai Cai , Ning Cai , Christian Deppe

The full solution of the optimization problem giving the Gaussian capacity of the single-mode fiducial Gaussian quantum channel is provided. Since it was shown that the Gaussian capacity of an arbitrary (phase-sensitive or insensitive)…

Quantum Physics · Physics 2016-09-19 Joachim Schäfer , Evgueni Karpov , Oleg V. Pilyavets , Nicolas J. Cerf

We discuss the estimation of channel parameters for a noisy quantum channel - the so-called Pauli channel - using finite resources. It turns out that prior entanglement considerably enhances the fidelity of the estimation when we compare it…

Quantum Physics · Physics 2009-11-07 Dietmar G. Fischer , Holger Mack , Markus A. Cirone , Matthias Freyberger

We analyze the quantum capacity of a unital quantum channel, using ideas from the proof of near-optimality of Petz recovery map [Barnum and Knill 2000] and give an upper bound on the quantum capacity in terms of regularized output $2$-norm…

Quantum Physics · Physics 2018-03-07 Anurag Anshu

We initiate the study of passive environment-assisted communication via a quantum channel, modeled as a unitary interaction between the information carrying system and an environment. In this model, the environment is controlled by a…

Quantum Physics · Physics 2016-03-25 Siddharth Karumanchi , Stefano Mancini , Andreas Winter , Dong Yang

The quantum capacity captures the value of a quantum channel for transmitting quantum information, establishing the fundamental limits on quantum communication. In spite of its central role in quantum information theory, the quantum…

We present a simple model of quantum communication where a noisy quantum channel may benefit from the addition of further noise at the decoding stage. We demonstrate enhancement of the classical information capacity of an amplitude damping…

Quantum Physics · Physics 2015-06-26 Garry Bowen , Stefano Mancini

We fully characterize the reduced dynamics of an open quantum system initially correlated with its environment. Using a photonic qubit coupled to a simulated environment we tomographically reconstruct a superchannel---a generalised channel…

We give a capacity formula for the classical information transmission over a noisy quantum channel, with separable encoding by the sender and limited resources provided by the receiver's pre-shared ancilla. Instead of a pure state, we…

Quantum Physics · Physics 2017-05-22 Quntao Zhuang , Elton Yechao Zhu , Peter W. Shor