English
Related papers

Related papers: Fidelity of Gaussian channels

200 papers

We generalize the experimental success criterion for quantum teleportation/memory in continuous-variable quantum systems to be suitable for non-unit-gain condition by considering attenuation/amplification of the coherent-state amplitude.…

Quantum Physics · Physics 2008-09-29 Ryo Namiki , Masato Koashi , Nobuyuki Imoto

We present a general theoretical formalism to compute the fidelity of transformations of unknown quantum states. We then focus on the case of Gaussian transformations of continuous variable quantum systems, where, for the case of a Gaussian…

Quantum Physics · Physics 2007-05-23 Lars Bojer Madsen , Klaus Molmer

Noise is the main obstacle for the realization of fault tolerant quantum information processing and secure communication over long distances. In this work, we propose a communication protocol relying on simple linear optics that optimally…

Quantum Physics · Physics 2015-06-16 Mikael Lassen , Adriano Berni , Lars S. Madsen , Radim Filip , Ulrik L. Andersen

We aim to devise feasible, efficient verification schemes for bosonic channels. To this end, we construct an average-fidelity witness that yields a tight lower bound for average fidelity plus a general framework for verifying optimal…

Quantum Physics · Physics 2019-07-19 Ya-Dong Wu , Barry C. Sanders

Two separated observers, by applying local operations to a supply of not-too-impure entangled states ({\em e.g.} singlets shared through a noisy channel), can prepare a smaller number of entangled pairs of arbitrarily high purity ({\em…

The employ of a noiseless linear amplifier (NLA) has been proven as a useful tool for mitigating imperfections in quantum channels. Its analysis is usually conducted within specific frameworks, for which the set of input states for a given…

Quantum Physics · Physics 2015-06-10 Rémi Blandino , Marco Barbieri , Philippe Grangier , Rosa Tualle-Brouri

We consider the problem of deterministically cloning quantum channels with respect to the best attainable rate and the highest quality, so-called optimal cloning. We demonstrate that cloning quantum states is, in-fact, equivalent to cloning…

The additivity problem asks if the use of entanglement can boost the information-carrying capacity of a given channel beyond what is achievable by coding with simple product states only. This has recently been shown not to be the case for…

Quantum Physics · Physics 2018-04-10 Stefan Huber , Robert Koenig

A quantum channel is derived for continuous variable teleportation which is performed by means of an arbitrary entangled state and the standard protocol. When a Gaussian entangled state such as a two-mode squeezed-vacuum state is used, the…

Quantum Physics · Physics 2009-11-07 Masashi Ban , Masahide Sasaki , Masahiro Takeoka

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 operations, or quantum channels cannot be inverted in general. An arbitrary state passing through a quantum channel looses its fidelity with the input. Given a quantum channel ${\cal E}$, we introduce the concept of its…

Quantum Physics · Physics 2020-03-25 Vahid Karimipour , Fabio Benatti , Roberto Floreanini

The set of quantum Gaussian channels acting on one bosonic mode can be classified according to the action of the group of Gaussian unitaries. We look for bounds on the classical capacity for channels belonging to such a classification.…

Quantum Physics · Physics 2011-03-03 Cosmo Lupo , Stefano Pirandola , Paolo Aniello , Stefano Mancini

We suggest and demonstrate an all-optical quantum simulator for single-qubit noisy channels originating from the interaction with a fluctuating field. The simulator employs the polarization degree of freedom of a single photon, and exploits…

Given a certain amount of entanglement available as a resource, what is the most efficient way to accomplish a quantum task? We address this question in the relevant case of continuous variable quantum teleportation protocols implemented…

Quantum Physics · Physics 2017-11-29 Pietro Liuzzo-Scorpo , Andrea Mari , Vittorio Giovannetti , Gerardo Adesso

We consider the problem of correcting the errors incurred from sending classical or quantum information through a noisy quantum environment by schemes using classical information obtained from a measurement on the environment. We give a…

Quantum Physics · Physics 2015-06-26 M. Gregoratti , R. F. Werner

We study the Kimble-Braunstein continuous-variable quantum teleportation with the quantum channel physically realized in the turbulent atmosphere. In this context, we examine the applicability of different strategies preserving the Gaussian…

Quantum Physics · Physics 2019-09-27 K. Hofmann , A. A. Semenov , W. Vogel , Martin Bohmann

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

The optimization of entanglement evolution for two-mode Gaussian pure states under one-side Gaussian map is studied. Even there isn't complete information about the one-side Gaussian noisy channel, one can still maximize the entanglement…

Quantum Physics · Physics 2015-05-14 Xiang-Bin Wang , Zong-Wen Yu , Jia-Zhong Hu

Biochemical signal transduction, a form of molecular communication, can be modeled using graphical Markov channels with input-modulated transition rates. Such channel models are strongly non-Gaussian. In this paper we use a linear noise…

Quantitative Methods · Quantitative Biology 2019-08-30 Gregory R. Hessler , Andrew W. Eckford , Peter J. Thomas

We propose a fidelity measure for quantum channels in a straightforward analogy to the corresponding mixed-state fidelity of Jozsa. We describe properties of this fidelity measure and discuss some applications of it to quantum information…

Quantum Physics · Physics 2007-05-23 Maxim Raginsky
‹ Prev 1 4 5 6 7 8 10 Next ›