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Related papers: Fidelity of Gaussian channels

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We prove that whenever the coherent information of a one-mode Gaussian channel is non-zero its supremum is achieved for the infinite input power. This is a well established fact for the zero added classical noise, whereas the nonzero case…

Quantum Physics · Physics 2016-02-08 Kamil Bradler

We derive an upper limit for the mixedness of single bosonic mode gaussian states propagating in dissipative channels. It is a function of the initial squeezing and temperature of the channel only. Moreover the time at which von Neumann's…

Quantum Physics · Physics 2008-08-07 Leonardo A. M. Souza , M. C. Nemes

The pure-loss channel is a fundamental model for describing noise in bosonic quantum platforms. It is characterised by a single parameter, the transmissivity, which quantifies the fraction of the input energy that reaches the output of the…

The possibility of stochastic resonance of a quantum channel and hence the noise enhanced quantum channel capacity is explored by considering one-Pauli channels which are more classical like. The fidelity of the channel is also considered.

Quantum Physics · Physics 2015-06-26 Julian Juhi-Lian Ting

For information transmission a discrete time channel with independent additive Gaussian noise is used. There is also another channel with independent additive Gaussian noise (the feedback channel), and the transmitter observes without delay…

Information Theory · Computer Science 2015-01-21 Marat V. Burnashev , Hirosuke Yamamoto

Quantum fidelity is a central tool in quantum information, quantifying how much two quantum states are similar. Here we propose a limit formula for the quantum fidelity between a mixed state and a pure state. As an example of an…

Quantum Physics · Physics 2014-10-13 Gaetana Spedalieri , Christian Weedbrook , Stefano Pirandola

The process of quantum teleportation can be considered as a quantum channel. The exact classical capacity of the continuous variable teleportation channel is given. Also, the channel fidelity is derived. Consequently, the properties of the…

Quantum Physics · Physics 2015-06-26 Tao Qin , Meisheng Zhao , Yongde Zhang

In this paper, we revisit the problem of finding the average capacity of the Gaussian feedback channel. First, we consider the problem of finding the average capacity of the analog Gaussian noise channel where the noise has an arbitrary…

Information Theory · Computer Science 2019-01-24 Ather Gattami

We consider quantum state transfer in a fully connected spin network, in which the results indicate that it is impossible to achieve high fidelity by free dynamics. However, the addition of certain kinds of noise can be helpful for this…

Quantum Physics · Physics 2015-06-16 Morteza Rafiee , Cosmo Lupo , Stefano Mancini

A generic quantum channel can be represented in terms of a unitary interaction between the information-carrying system and a noisy environment. Here, the minimal number of quantum Gaussian environmental modes required to provide a unitary…

Quantum Physics · Physics 2015-05-19 Filippo Caruso , Jens Eisert , Vittorio Giovannetti , Alexander S. Holevo

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

For a continuous-input-continuous-output arbitrarily distributed quantum channel carrying classical information, the channel capacity can be computed in terms of the distribution of the channel envelope, received signal strength over a…

Information Theory · Computer Science 2022-06-09 Mouli Chakraborty , Harun Siljak , Indrakshi Dey , Nicola Marchetti

The most natural way to describe an information-carrying system containing a specific noise is an additive white Gaussian-noise (AWGN) channel. In bosonic quantum systems (especially the Gaussian case), although the classical information…

Quantum Physics · Physics 2019-05-14 Kabgyun Jeong , Hun Hee Lee , Youngrong Lim

We extend the research program initiated in [Phys. Rev. A 92, 012338 (2015)], where we restricted our attention to noisy deterministic teleportation protocols, to noisy probabilistic (conditional) protocols. Our main goal now is to study…

Quantum Physics · Physics 2016-06-27 Raphael Fortes , Gustavo Rigolin

Under rather general assumptions about the properties of a noisy quantum channel, a first quantum protocol is proposed which allows to implement the secret bit commitment with the probability arbitrarily close to unity.

Quantum Physics · Physics 2007-05-23 S. N. Molotkov , S. S. Nazin

The long-standing conjectures of the optimality of Gaussian inputs for Gaussian channel and Gaussian additivity are solved for a broad class of covariant or contravariant Bosonic Gaussian channels (which includes in particular thermal,…

Quantum Physics · Physics 2015-03-04 V. Giovannetti , A. S. Holevo , R. Garcia-Patron

The statistical complexity of continuous-variable quantum states can be characterized with a quantifier defined in terms of information-theoretic quantities derived from the Husimi Q-function. In this work, we utilize this complexity…

Quantum Physics · Physics 2026-03-04 Siting Tang , Francesco Albarelli , Yue Zhang , Shunlong Luo , Matteo G. A. Paris

Quantum teleportation is one of the most pioneering features of the quantum world. Typically, the quality of a teleportation protocol is solely judged by its average fidelity. In this work, we analyze the performance of teleportation in…

Quantum Physics · Physics 2020-08-03 Saptarshi Roy , Arkaprabha Ghosal

In this paper we are interested to model quantum signal by statistical signal processing methods. The Gaussian distribution has been considered for the input quantum signal as Gaussian state have been proven to a type of important robust…

Quantum Physics · Physics 2023-02-17 Mouli Chakraborty , Harun Siljak , Indrakshi Dey , Nicola Marchetti

The purpose of this work is to extend the result of previous papers quant-ph/9611023, quant-ph/9703013 to quantum channels with additive constraints onto the input signal, by showing that the capacity of such channel is equal to the…

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